diff --git a/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/XMLWorkspaceService.java b/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/XMLWorkspaceService.java
index b9651d72a3..38720a3f0d 100644
--- a/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/XMLWorkspaceService.java
+++ b/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/XMLWorkspaceService.java
@@ -63,7 +63,7 @@ public CompletableFuture<Object> executeCommand(ExecuteCommandParams params) {
 			}
 			return CompletableFutures.computeAsync(cancelChecker -> {
 				try {
-					return handler.executeCommand(params, cancelChecker);
+					return handler.executeCommand(params, xmlLanguageServer.getSharedSettings(), cancelChecker);
 				} catch (Exception e) {
 					if (e instanceof ResponseErrorException) {
 						throw (ResponseErrorException) e;
diff --git a/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/ContentModelPlugin.java b/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/ContentModelPlugin.java
index 40f6f1f913..6f95811ab8 100644
--- a/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/ContentModelPlugin.java
+++ b/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/ContentModelPlugin.java
@@ -15,10 +15,12 @@
 import java.util.Objects;
 
 import org.eclipse.lemminx.dom.DOMDocument;
+import org.eclipse.lemminx.extensions.contentmodel.commands.AssociateGrammarCommand;
 import org.eclipse.lemminx.extensions.contentmodel.commands.XMLValidationAllFilesCommand;
 import org.eclipse.lemminx.extensions.contentmodel.commands.XMLValidationFileCommand;
 import org.eclipse.lemminx.extensions.contentmodel.model.ContentModelManager;
 import org.eclipse.lemminx.extensions.contentmodel.participants.ContentModelCodeActionParticipant;
+import org.eclipse.lemminx.extensions.contentmodel.participants.ContentModelCodeLensParticipant;
 import org.eclipse.lemminx.extensions.contentmodel.participants.ContentModelCompletionParticipant;
 import org.eclipse.lemminx.extensions.contentmodel.participants.ContentModelDocumentLinkParticipant;
 import org.eclipse.lemminx.extensions.contentmodel.participants.ContentModelHoverParticipant;
@@ -36,6 +38,7 @@
 import org.eclipse.lemminx.services.extensions.ITypeDefinitionParticipant;
 import org.eclipse.lemminx.services.extensions.IXMLExtension;
 import org.eclipse.lemminx.services.extensions.XMLExtensionsRegistry;
+import org.eclipse.lemminx.services.extensions.codelens.ICodeLensParticipant;
 import org.eclipse.lemminx.services.extensions.commands.IXMLCommandService;
 import org.eclipse.lemminx.services.extensions.diagnostics.IDiagnosticsParticipant;
 import org.eclipse.lemminx.services.extensions.save.ISaveContext;
@@ -68,6 +71,8 @@ public class ContentModelPlugin implements IXMLExtension {
 
 	private ContentModelSymbolsProviderParticipant symbolsProviderParticipant;
 
+	private final ICodeLensParticipant codeLensParticipant;
+
 	ContentModelManager contentModelManager;
 
 	private ContentModelSettings cmSettings;
@@ -80,6 +85,7 @@ public ContentModelPlugin() {
 		diagnosticsParticipant = new ContentModelDiagnosticsParticipant(this);
 		codeActionParticipant = new ContentModelCodeActionParticipant();
 		typeDefinitionParticipant = new ContentModelTypeDefinitionParticipant();
+		codeLensParticipant = new ContentModelCodeLensParticipant();
 	}
 
 	@Override
@@ -176,6 +182,7 @@ public void start(InitializeParams params, XMLExtensionsRegistry registry) {
 		registry.registerTypeDefinitionParticipant(typeDefinitionParticipant);
 		symbolsProviderParticipant = new ContentModelSymbolsProviderParticipant(contentModelManager);
 		registry.registerSymbolsProviderParticipant(symbolsProviderParticipant);
+		registry.registerCodeLensParticipant(codeLensParticipant);
 
 		// Register custom commands to re-validate XML files
 		IXMLCommandService commandService = registry.getCommandService();
@@ -186,6 +193,8 @@ public void start(InitializeParams params, XMLExtensionsRegistry registry) {
 					new XMLValidationFileCommand(contentModelManager, documentProvider, validationService));
 			commandService.registerCommand(XMLValidationAllFilesCommand.COMMAND_ID,
 					new XMLValidationAllFilesCommand(contentModelManager, documentProvider, validationService));
+			commandService.registerCommand(AssociateGrammarCommand.COMMAND_ID,
+					new AssociateGrammarCommand(documentProvider));
 		}
 	}
 
@@ -198,12 +207,14 @@ public void stop(XMLExtensionsRegistry registry) {
 		registry.unregisterDocumentLinkParticipant(documentLinkParticipant);
 		registry.unregisterTypeDefinitionParticipant(typeDefinitionParticipant);
 		registry.unregisterSymbolsProviderParticipant(symbolsProviderParticipant);
+		registry.unregisterCodeLensParticipant(codeLensParticipant);
 
 		// Un-register custom commands to re-validate XML files
 		IXMLCommandService commandService = registry.getCommandService();
 		if (commandService != null) {
 			commandService.unregisterCommand(XMLValidationFileCommand.COMMAND_ID);
 			commandService.unregisterCommand(XMLValidationAllFilesCommand.COMMAND_ID);
+			commandService.unregisterCommand(AssociateGrammarCommand.COMMAND_ID);
 		}
 	}
 
diff --git a/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/commands/AssociateGrammarCommand.java b/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/commands/AssociateGrammarCommand.java
new file mode 100644
index 0000000000..28d5ae622b
--- /dev/null
+++ b/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/commands/AssociateGrammarCommand.java
@@ -0,0 +1,143 @@
+/*******************************************************************************
+* Copyright (c) 2021 Red Hat Inc. and others.
+* All rights reserved. This program and the accompanying materials
+* which accompanies this distribution, and is available at
+* http://www.eclipse.org/legal/epl-v20.html
+*
+* SPDX-License-Identifier: EPL-2.0
+*
+* Contributors:
+*     Red Hat Inc. - initial API and implementation
+*******************************************************************************/
+package org.eclipse.lemminx.extensions.contentmodel.commands;
+
+import static org.eclipse.lemminx.extensions.xsd.utils.XSDUtils.TARGET_NAMESPACE_ATTR;
+
+import java.net.URL;
+import java.nio.file.Path;
+
+import javax.xml.parsers.SAXParser;
+import javax.xml.parsers.SAXParserFactory;
+
+import org.eclipse.lemminx.dom.DOMDocument;
+import org.eclipse.lemminx.extensions.contentmodel.participants.codeactions.NoGrammarConstraintsCodeAction;
+import org.eclipse.lemminx.services.IXMLDocumentProvider;
+import org.eclipse.lemminx.services.extensions.commands.AbstractDOMDocumentCommandHandler;
+import org.eclipse.lemminx.services.extensions.commands.ArgumentsUtils;
+import org.eclipse.lemminx.settings.SharedSettings;
+import org.eclipse.lemminx.utils.FilesUtils;
+import org.eclipse.lemminx.utils.StringUtils;
+import org.eclipse.lsp4j.ExecuteCommandParams;
+import org.eclipse.lsp4j.jsonrpc.CancelChecker;
+import org.xml.sax.Attributes;
+import org.xml.sax.SAXException;
+import org.xml.sax.helpers.DefaultHandler;
+
+/**
+ * Associate a grammar to a given XML command.
+ * 
+ * @author Angelo ZERR
+ *
+ */
+public class AssociateGrammarCommand extends AbstractDOMDocumentCommandHandler {
+
+	public static final String COMMAND_ID = "xml.associate.grammar.insert";
+
+	public AssociateGrammarCommand(IXMLDocumentProvider documentProvider) {
+		super(documentProvider);
+	}
+
+	public enum GrammarBindingType {
+
+		XSD("xsd"), //
+		DTD("dtd"), //
+		XML_MODEL("xml-model");
+
+		private String name;
+
+		private GrammarBindingType(String name) {
+			this.name = name != null ? name : name();
+		}
+
+		public String getName() {
+			return name;
+		}
+	}
+
+	@Override
+	protected Object executeCommand(DOMDocument document, ExecuteCommandParams params, SharedSettings sharedSettings,
+			CancelChecker cancelChecker) throws Exception {
+		String documentURI = document.getDocumentURI();
+		String fullPathGrammarURI = ArgumentsUtils.getArgAt(params, 1, String.class);
+		String bindingType = ArgumentsUtils.getArgAt(params, 2, String.class);
+		String grammarURI = getRelativeURI(fullPathGrammarURI, documentURI);
+
+		if (GrammarBindingType.XSD.getName().equals(bindingType)) {
+			// Check if XSD to bind declares a target namespace
+			String targetNamespace = getTargetNamespace(fullPathGrammarURI);
+			if (StringUtils.isEmpty(targetNamespace)) {
+				// Insert inside <foo /> ->
+				// xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance"
+				// xsi:noNamespaceSchemaLocation=\"xsd/tag.xsd\"
+				return NoGrammarConstraintsCodeAction.createXSINoNamespaceSchemaLocationEdit(grammarURI, document);
+			}
+			// Insert inside <foo /> ->
+			// xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+			// xsi:noNamespaceSchemaLocation="xsd/tag.xsd"
+			return NoGrammarConstraintsCodeAction.createXSISchemaLocationEdit(grammarURI, targetNamespace, document);
+		} else if (GrammarBindingType.DTD.getName().equals(bindingType)) {
+			// Insert before <foo /> -> <!DOCTYPE foo SYSTEM "dtd/tag.dtd">
+			return NoGrammarConstraintsCodeAction.createDocTypeEdit(grammarURI, document, sharedSettings);
+		} else if (GrammarBindingType.XML_MODEL.getName().equals(bindingType)) {
+			// Insert before <foo /> -> <?xml-model href=\"dtd/tag.dtd\"?>
+			return NoGrammarConstraintsCodeAction.createXmlModelEdit(grammarURI, document, sharedSettings);
+		}
+		return null;
+	}
+
+	private static String getRelativeURI(String fullPathGrammarURI, String documentURI) {
+		try {
+			Path grammarPath = FilesUtils.getPath(fullPathGrammarURI);
+			Path documentPath = FilesUtils.getPath(documentURI);
+			Path relativePath = documentPath.getParent().relativize(grammarPath);
+			return relativePath.toString().replaceAll("[\\\\]", "/");
+		} catch (Exception e) {
+			return fullPathGrammarURI;
+		}
+	}
+
+	private static String getTargetNamespace(String xsdURI) {
+		TargetNamespaceHandler handler = new TargetNamespaceHandler();
+		try {
+			SAXParserFactory factory = SAXParserFactory.newInstance();
+			SAXParser saxParser = factory.newSAXParser();
+			saxParser.parse(new URL(xsdURI).openStream(), handler);
+		} catch (Exception e) {
+
+		}
+		return handler.getTargetNamespace();
+	}
+
+	/**
+	 * SAX handler which extract the targetNamespace attribute from the xs:schema
+	 * root tag element and null otherwise.
+	 *
+	 */
+	private static class TargetNamespaceHandler extends DefaultHandler {
+
+		private String targetNamespace;
+
+		@Override
+		public void startElement(String uri, String localName, String qName, Attributes attributes)
+				throws SAXException {
+			super.startElement(uri, localName, qName, attributes);
+			this.targetNamespace = attributes.getValue(TARGET_NAMESPACE_ATTR);
+			throw new SAXException();
+		}
+
+		public String getTargetNamespace() {
+			return targetNamespace;
+		}
+	}
+
+}
diff --git a/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/commands/XMLValidationAllFilesCommand.java b/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/commands/XMLValidationAllFilesCommand.java
index ef05dd92a1..0a8d39900a 100644
--- a/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/commands/XMLValidationAllFilesCommand.java
+++ b/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/commands/XMLValidationAllFilesCommand.java
@@ -18,6 +18,7 @@
 import org.eclipse.lemminx.services.IXMLDocumentProvider;
 import org.eclipse.lemminx.services.IXMLValidationService;
 import org.eclipse.lemminx.services.extensions.commands.IXMLCommandService.IDelegateCommandHandler;
+import org.eclipse.lemminx.settings.SharedSettings;
 import org.eclipse.lsp4j.ExecuteCommandParams;
 import org.eclipse.lsp4j.jsonrpc.CancelChecker;
 
@@ -52,7 +53,8 @@ public XMLValidationAllFilesCommand(ContentModelManager contentModelManager, IXM
 	}
 
 	@Override
-	public Object executeCommand(ExecuteCommandParams params, CancelChecker cancelChecker) throws Exception {
+	public Object executeCommand(ExecuteCommandParams params, SharedSettings sharedSettings,
+			CancelChecker cancelChecker) throws Exception {
 		// 1. clear the Xerces grammar pool
 		// (used by the Xerces validation) and the content model documents cache (used
 		// by the XML completion/hover based on the grammar)
diff --git a/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/commands/XMLValidationFileCommand.java b/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/commands/XMLValidationFileCommand.java
index b6d4d56698..06c07d2cc2 100644
--- a/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/commands/XMLValidationFileCommand.java
+++ b/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/commands/XMLValidationFileCommand.java
@@ -16,6 +16,7 @@
 import org.eclipse.lemminx.services.IXMLDocumentProvider;
 import org.eclipse.lemminx.services.IXMLValidationService;
 import org.eclipse.lemminx.services.extensions.commands.AbstractDOMDocumentCommandHandler;
+import org.eclipse.lemminx.settings.SharedSettings;
 import org.eclipse.lsp4j.ExecuteCommandParams;
 import org.eclipse.lsp4j.jsonrpc.CancelChecker;
 
@@ -48,8 +49,8 @@ public XMLValidationFileCommand(ContentModelManager contentModelManager, IXMLDoc
 	}
 
 	@Override
-	protected Object executeCommand(DOMDocument document, ExecuteCommandParams params, CancelChecker cancelChecker)
-			throws Exception {
+	protected Object executeCommand(DOMDocument document, ExecuteCommandParams params, SharedSettings sharedSettings,
+			CancelChecker cancelChecker) throws Exception {
 		// 1. remove the referenced grammar in the XML file from the Xerces grammar pool
 		// (used by the Xerces validation) and the content model documents cache (used
 		// by the XML completion/hover based on the grammar)
diff --git a/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/participants/ContentModelCodeLensParticipant.java b/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/participants/ContentModelCodeLensParticipant.java
new file mode 100644
index 0000000000..ec0eeee61d
--- /dev/null
+++ b/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/participants/ContentModelCodeLensParticipant.java
@@ -0,0 +1,74 @@
+/*******************************************************************************
+* Copyright (c) 2021 Red Hat Inc. and others.
+* All rights reserved. This program and the accompanying materials
+* which accompanies this distribution, and is available at
+* http://www.eclipse.org/legal/epl-v20.html
+*
+* SPDX-License-Identifier: EPL-2.0
+*
+* Contributors:
+*     Red Hat Inc. - initial API and implementation
+*******************************************************************************/
+
+package org.eclipse.lemminx.extensions.contentmodel.participants;
+
+import java.util.Arrays;
+import java.util.List;
+
+import org.eclipse.lemminx.dom.DOMDocument;
+import org.eclipse.lemminx.dom.DOMElement;
+import org.eclipse.lemminx.extensions.contentmodel.commands.AssociateGrammarCommand;
+import org.eclipse.lemminx.extensions.contentmodel.commands.AssociateGrammarCommand.GrammarBindingType;
+import org.eclipse.lemminx.services.extensions.codelens.ICodeLensParticipant;
+import org.eclipse.lemminx.services.extensions.codelens.ICodeLensRequest;
+import org.eclipse.lemminx.utils.XMLPositionUtility;
+import org.eclipse.lsp4j.CodeLens;
+import org.eclipse.lsp4j.Command;
+import org.eclipse.lsp4j.Range;
+import org.eclipse.lsp4j.jsonrpc.CancelChecker;
+
+/**
+ * When XML file is not associated to a grammar (XSD, DTD), this class generates
+ * several CodeLenses on the root of the DOM Document:
+ * 
+ * <ul>
+ * <li>[Bind with XSD] : click on this Codelens open a folder dialog to select
+ * the XSD to bind.</li>
+ * <li>[Bind with DTD] : click on this Codelens open a folder dialog to select
+ * the DTD to bind.</li>
+ * <li>[Bind with xml-model] : click on this Codelens open a folder dialog to
+ * select the XSD, DTD to bind.</li>
+ * </ul>
+ * 
+ * <p>
+ * Once the LSP client select the DTD, XSD, it should call the
+ * {@link AssociateGrammarCommand} to generate the proper syntax for binding.
+ * </p>
+ *
+ */
+public class ContentModelCodeLensParticipant implements ICodeLensParticipant {
+
+	private static final String COMMAND_ID = "xml.associate.grammar.selectFile";
+
+	@Override
+	public void doCodeLens(ICodeLensRequest request, List<CodeLens> lenses, CancelChecker cancelChecker) {
+		DOMDocument document = request.getDocument();
+		DOMElement documentElement = document.getDocumentElement();
+		if (documentElement == null || document.hasGrammar()) {
+			return;
+		}
+		String documentURI = document.getDocumentURI();
+		Range range = XMLPositionUtility.selectRootStartTag(document);
+
+		lenses.add(createAssociateLens(documentURI, "Bind with XSD", GrammarBindingType.XSD.getName(), range));
+		lenses.add(createAssociateLens(documentURI, "Bind with DTD", GrammarBindingType.DTD.getName(), range));
+		lenses.add(
+				createAssociateLens(documentURI, "Bind with xml-model", GrammarBindingType.XML_MODEL.getName(), range));
+	}
+
+	private static CodeLens createAssociateLens(String documentURI, String title, String bindingType, Range range) {
+		Command command = new Command(title, COMMAND_ID, Arrays.asList(documentURI, bindingType));
+		return new CodeLens(range, command, null);
+	}
+
+}
diff --git a/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/participants/DTDErrorCode.java b/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/participants/DTDErrorCode.java
index 9ca2845b4e..64cfe221b2 100644
--- a/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/participants/DTDErrorCode.java
+++ b/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/participants/DTDErrorCode.java
@@ -20,7 +20,6 @@
 import org.apache.xerces.xni.XMLLocator;
 import org.eclipse.lemminx.commons.BadLocationException;
 import org.eclipse.lemminx.dom.DOMDocument;
-import org.eclipse.lemminx.dom.DOMDocumentType;
 import org.eclipse.lemminx.dom.DOMElement;
 import org.eclipse.lemminx.dom.DOMRange;
 import org.eclipse.lemminx.extensions.contentmodel.participants.codeactions.ElementDeclUnterminatedCodeAction;
diff --git a/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/participants/codeactions/NoGrammarConstraintsCodeAction.java b/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/participants/codeactions/NoGrammarConstraintsCodeAction.java
index ce5ced722b..5a10386a86 100644
--- a/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/participants/codeactions/NoGrammarConstraintsCodeAction.java
+++ b/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/participants/codeactions/NoGrammarConstraintsCodeAction.java
@@ -55,9 +55,6 @@ public void doCodeAction(Diagnostic diagnostic, Range range, DOMDocument documen
 			}
 
 			FileContentGeneratorManager generator = componentProvider.getComponent(FileContentGeneratorManager.class);
-			String delimiter = document.lineDelimiter(0);
-			int beforeTagOffset = documentElement.getStartTagOpenOffset();
-			int afterTagOffset = beforeTagOffset + 1 + documentElement.getTagName().length();
 
 			// ---------- XSD
 
@@ -67,23 +64,18 @@ public void doCodeAction(Diagnostic diagnostic, Range range, DOMDocument documen
 
 			// xsi:noNamespaceSchemaLocation
 			// Create code action to create the XSD file with the generated XSD content
-			String insertText = " xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\""
-					+ document.getTextDocument().lineDelimiter(0);
-			insertText += " xsi:noNamespaceSchemaLocation=\"" + schemaFileName + "\"";
+			TextDocumentEdit noNamespaceSchemaLocationEdit = createXSINoNamespaceSchemaLocationEdit(schemaFileName,
+					document);
 			CodeAction noNamespaceSchemaLocationAction = createGrammarFileAndBindIt(
 					"Generate '" + schemaFileName + "' and bind with xsi:noNamespaceSchemaLocation", schemaURI,
-					schemaTemplate, insertText, afterTagOffset, document, diagnostic);
+					schemaTemplate, noNamespaceSchemaLocationEdit, diagnostic);
 			codeActions.add(noNamespaceSchemaLocationAction);
 
 			// xml-model
-			XMLBuilder xsdWithXmlModel = new XMLBuilder(sharedSettings, null, delimiter);
-			xsdWithXmlModel.startPrologOrPI("xml-model");
-			xsdWithXmlModel.addSingleAttribute("href", schemaFileName, true);
-			xsdWithXmlModel.endPrologOrPI();
-			xsdWithXmlModel.linefeed();
+			TextDocumentEdit xsdWithXMLModelEdit = createXmlModelEdit(schemaFileName, document, sharedSettings);
 			CodeAction xsdWithXmlModelAction = createGrammarFileAndBindIt(
 					"Generate '" + schemaFileName + "' and bind with xml-model", schemaURI, schemaTemplate,
-					xsdWithXmlModel.toString(), beforeTagOffset, document, diagnostic);
+					xsdWithXMLModelEdit, diagnostic);
 			codeActions.add(xsdWithXmlModelAction);
 
 			// ---------- DTD
@@ -93,28 +85,17 @@ public void doCodeAction(Diagnostic diagnostic, Range range, DOMDocument documen
 			String dtdTemplate = generator.generate(document, sharedSettings, new DTDGeneratorSettings());
 
 			// <!DOCTYPE ${1:root-element} SYSTEM \"${2:file}.dtd\">
-			XMLBuilder docType = new XMLBuilder(sharedSettings, null, delimiter);
-			docType.startDoctype();
-			docType.addParameter(documentElement.getLocalName());
-			docType.addContent(" SYSTEM \"");
-			docType.addContent(dtdFileName);
-			docType.addContent("\"");
-			docType.endDoctype();
-			docType.linefeed();
+			TextDocumentEdit dtdWithDocType = createDocTypeEdit(dtdFileName, document, sharedSettings);
 			CodeAction docTypeAction = createGrammarFileAndBindIt(
-					"Generate '" + dtdFileName + "' and bind with DOCTYPE", dtdURI, dtdTemplate, docType.toString(),
-					beforeTagOffset, document, diagnostic);
+					"Generate '" + dtdFileName + "' and bind with DOCTYPE", dtdURI, dtdTemplate, dtdWithDocType,
+					diagnostic);
 			codeActions.add(docTypeAction);
 
 			// xml-model
-			XMLBuilder dtdWithXmlModel = new XMLBuilder(sharedSettings, null, delimiter);
-			dtdWithXmlModel.startPrologOrPI("xml-model");
-			dtdWithXmlModel.addSingleAttribute("href", dtdFileName, true);
-			dtdWithXmlModel.endPrologOrPI();
-			dtdWithXmlModel.linefeed();
+			TextDocumentEdit dtdWithXMLModelEdit = createXmlModelEdit(dtdFileName, document, sharedSettings);
 			CodeAction dtdWithXmlModelAction = createGrammarFileAndBindIt(
-					"Generate '" + dtdFileName + "' and bind with xml-model", dtdURI, dtdTemplate,
-					dtdWithXmlModel.toString(), beforeTagOffset, document, diagnostic);
+					"Generate '" + dtdFileName + "' and bind with xml-model", dtdURI, dtdTemplate, dtdWithXMLModelEdit,
+					diagnostic);
 			codeActions.add(dtdWithXmlModelAction);
 
 		} catch (BadLocationException e) {
@@ -153,18 +134,94 @@ static String getFileName(String schemaURI) {
 		return new File(schemaURI).getName();
 	}
 
-	private static CodeAction createGrammarFileAndBindIt(String title, String grammarURI, String grammarContent,
-			String insertText, int insertOffset, DOMDocument document, Diagnostic diagnostic)
-			throws BadLocationException {
-		Position position = document.positionAt(insertOffset);
-		TextDocumentEdit insertEdit = CodeActionFactory.insertEdit(insertText, position, document.getTextDocument());
-		return createGrammarFileAndBindIt(title, grammarURI, grammarContent, insertEdit, diagnostic);
-	}
-
 	private static CodeAction createGrammarFileAndBindIt(String title, String grammarURI, String grammarContent,
 			TextDocumentEdit boundEdit, Diagnostic diagnostic) {
 		CodeAction codeAction = CodeActionFactory.createFile(title, grammarURI, grammarContent, diagnostic);
 		codeAction.getEdit().getDocumentChanges().add(Either.forLeft(boundEdit));
 		return codeAction;
 	}
+
+	public static TextDocumentEdit createXSINoNamespaceSchemaLocationEdit(String schemaFileName, DOMDocument document)
+			throws BadLocationException {
+		String delimiter = document.getTextDocument().lineDelimiter(0);
+		DOMElement documentElement = document.getDocumentElement();
+		int beforeTagOffset = documentElement.getStartTagOpenOffset();
+		int afterTagOffset = beforeTagOffset + 1 + documentElement.getTagName().length();
+
+		StringBuilder insertText = new StringBuilder();
+		
+		insertText.append(" xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\"");
+		insertText.append(delimiter);
+
+		insertText.append(" xsi:noNamespaceSchemaLocation=\"");
+		insertText.append(schemaFileName);
+		insertText.append("\"");
+
+		Position position = document.positionAt(afterTagOffset);
+		return CodeActionFactory.insertEdit(insertText.toString(), position, document.getTextDocument());
+	}
+
+	public static TextDocumentEdit createXSISchemaLocationEdit(String schemaFileName, String targetNamespace,
+			DOMDocument document) throws BadLocationException {
+		String delimiter = document.getTextDocument().lineDelimiter(0);
+		DOMElement documentElement = document.getDocumentElement();
+		int beforeTagOffset = documentElement.getStartTagOpenOffset();
+		int afterTagOffset = beforeTagOffset + 1 + documentElement.getTagName().length();
+
+		StringBuilder insertText = new StringBuilder();
+		insertText.append(" xmlns=\"");
+		insertText.append(targetNamespace);
+		insertText.append("\"");
+		insertText.append(delimiter);
+		
+		insertText.append(" xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\"");
+		insertText.append(delimiter);
+
+		insertText.append(" xsi:schemaLocation=\"");
+		insertText.append(targetNamespace);
+		insertText.append(" ");
+		insertText.append(schemaFileName);
+		insertText.append("\"");
+		
+		Position position = document.positionAt(afterTagOffset);
+		return CodeActionFactory.insertEdit(insertText.toString(), position, document.getTextDocument());
+	}
+
+	public static TextDocumentEdit createXmlModelEdit(String schemaFileName, DOMDocument document,
+			SharedSettings sharedSettings) throws BadLocationException {
+		String delimiter = document.getTextDocument().lineDelimiter(0);
+		DOMElement documentElement = document.getDocumentElement();
+		int beforeTagOffset = documentElement.getStartTagOpenOffset();
+
+		XMLBuilder xsdWithXmlModel = new XMLBuilder(sharedSettings, null, delimiter);
+		xsdWithXmlModel.startPrologOrPI("xml-model");
+		xsdWithXmlModel.addSingleAttribute("href", schemaFileName, true);
+		xsdWithXmlModel.endPrologOrPI();
+		xsdWithXmlModel.linefeed();
+
+		String insertText = xsdWithXmlModel.toString();
+		Position position = document.positionAt(beforeTagOffset);
+		return CodeActionFactory.insertEdit(insertText, position, document.getTextDocument());
+	}
+
+	public static TextDocumentEdit createDocTypeEdit(String dtdFileName, DOMDocument document,
+			SharedSettings sharedSettings) throws BadLocationException {
+		String delimiter = document.getTextDocument().lineDelimiter(0);
+		DOMElement documentElement = document.getDocumentElement();
+		int beforeTagOffset = documentElement.getStartTagOpenOffset();
+
+		XMLBuilder docType = new XMLBuilder(sharedSettings, null, delimiter);
+		docType.startDoctype();
+		docType.addParameter(documentElement.getLocalName());
+		docType.addContent(" SYSTEM \"");
+		docType.addContent(dtdFileName);
+		docType.addContent("\"");
+		docType.endDoctype();
+		docType.linefeed();
+
+		String insertText = docType.toString();
+		Position position = document.positionAt(beforeTagOffset);
+		return CodeActionFactory.insertEdit(insertText, position, document.getTextDocument());
+	}
+
 }
diff --git a/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/xsd/utils/XSDUtils.java b/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/xsd/utils/XSDUtils.java
index 911bc5b279..f7ea55e0b2 100644
--- a/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/xsd/utils/XSDUtils.java
+++ b/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/xsd/utils/XSDUtils.java
@@ -47,6 +47,9 @@
  */
 public class XSDUtils {
 
+	public static final String SCHEMA_LOCATION_ATTR = "schemaLocation";
+	public static final String TARGET_NAMESPACE_ATTR = "targetNamespace";
+
 	/**
 	 * Binding type of xs attribute.
 	 *
@@ -152,7 +155,7 @@ public static void searchXSTargetAttributes(DOMAttr originAttr, BindingType bind
 		// <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
 		// xmlns:tns="http://camel.apache.org/schema/spring"
 		// targetNamespace="http://camel.apache.org/schema/spring" version="1.0">
-		String targetNamespace = documentElement.getAttribute("targetNamespace"); // ->
+		String targetNamespace = documentElement.getAttribute(TARGET_NAMESPACE_ATTR); // ->
 																					// http://camel.apache.org/schema/spring
 		String targetNamespacePrefix = documentElement.getPrefix(targetNamespace); // -> tns
 
@@ -190,7 +193,7 @@ private static void searchXSTargetAttributes(DOMAttr originAttr, BindingType bin
 					}
 				} else if (isXSInclude(targetElement)) {
 					// collect xs:include XML Schema location
-					String schemaLocation = targetElement.getAttribute("schemaLocation");
+					String schemaLocation = targetElement.getAttribute(SCHEMA_LOCATION_ATTR);
 					if (schemaLocation != null) {
 						if (externalURIS == null) {
 							externalURIS = new HashSet<>();
@@ -271,7 +274,7 @@ public static void searchXSOriginAttributes(DOMNode targetNode, BiConsumer<DOMAt
 		// <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
 		// xmlns:tns="http://camel.apache.org/schema/spring"
 		// targetNamespace="http://camel.apache.org/schema/spring" version="1.0">
-		String targetNamespace = documentElement.getAttribute("targetNamespace"); // ->
+		String targetNamespace = documentElement.getAttribute(TARGET_NAMESPACE_ATTR); // ->
 																					// http://camel.apache.org/schema/spring
 		String targetNamespacePrefix = documentElement.getPrefix(targetNamespace); // -> tns
 
@@ -464,7 +467,7 @@ public static DOMAttr getSchemaLocation(DOMElement element) {
 		if (!(isXSInclude(element) || isXSImport(element))) {
 			return null;
 		}
-		return element.getAttributeNode("schemaLocation");
+		return element.getAttributeNode(SCHEMA_LOCATION_ATTR);
 	}
 
 }
diff --git a/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/services/extensions/commands/AbstractDOMDocumentCommandHandler.java b/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/services/extensions/commands/AbstractDOMDocumentCommandHandler.java
index 140a47af31..a031fed6d8 100644
--- a/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/services/extensions/commands/AbstractDOMDocumentCommandHandler.java
+++ b/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/services/extensions/commands/AbstractDOMDocumentCommandHandler.java
@@ -14,6 +14,7 @@
 import org.eclipse.lemminx.dom.DOMDocument;
 import org.eclipse.lemminx.services.IXMLDocumentProvider;
 import org.eclipse.lemminx.services.extensions.commands.IXMLCommandService.IDelegateCommandHandler;
+import org.eclipse.lemminx.settings.SharedSettings;
 import org.eclipse.lsp4j.ExecuteCommandParams;
 import org.eclipse.lsp4j.TextDocumentIdentifier;
 import org.eclipse.lsp4j.jsonrpc.CancelChecker;
@@ -34,7 +35,8 @@ public AbstractDOMDocumentCommandHandler(IXMLDocumentProvider documentProvider)
 	}
 
 	@Override
-	public final Object executeCommand(ExecuteCommandParams params, CancelChecker cancelChecker) throws Exception {
+	public final Object executeCommand(ExecuteCommandParams params, SharedSettings sharedSettings,
+			CancelChecker cancelChecker) throws Exception {
 		TextDocumentIdentifier identifier = ArgumentsUtils.getArgAt(params, 0, TextDocumentIdentifier.class);
 		String uri = identifier.getUri();
 		DOMDocument document = documentProvider.getDocument(uri);
@@ -42,23 +44,24 @@ public final Object executeCommand(ExecuteCommandParams params, CancelChecker ca
 			throw new UnsupportedOperationException(String
 					.format("Command '%s' cannot find the DOM document with the URI '%s'.", params.getCommand(), uri));
 		}
-		return executeCommand(document, params, cancelChecker);
+		return executeCommand(document, params, sharedSettings, cancelChecker);
 	}
 
 	/**
 	 * Executes a command
 	 * 
-	 * @param document      the DOM document retrieve by the
-	 *                      {@link TextDocumentIdentifier} argument.
+	 * @param document       the DOM document retrieve by the
+	 *                       {@link TextDocumentIdentifier} argument.
 	 * 
-	 * @param params        command execution parameters
-	 * @param cancelChecker check if cancel has been requested
+	 * @param params         command execution parameters
+	 * @param sharedSettings the shared settings
+	 * @param cancelChecker  check if cancel has been requested
 	 * @return the result of the command
 	 * @throws Exception the unhandled exception will be wrapped in
 	 *                   <code>org.eclipse.lsp4j.jsonrpc.ResponseErrorException</code>
 	 *                   and be wired back to the JSON-RPC protocol caller
 	 */
 	protected abstract Object executeCommand(DOMDocument document, ExecuteCommandParams params,
-			CancelChecker cancelChecker) throws Exception;
+			SharedSettings sharedSettings, CancelChecker cancelChecker) throws Exception;
 
 }
\ No newline at end of file
diff --git a/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/services/extensions/commands/IXMLCommandService.java b/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/services/extensions/commands/IXMLCommandService.java
index 3940660de7..6e95461683 100644
--- a/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/services/extensions/commands/IXMLCommandService.java
+++ b/org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/services/extensions/commands/IXMLCommandService.java
@@ -14,6 +14,7 @@
 
 import java.util.concurrent.CompletableFuture;
 
+import org.eclipse.lemminx.settings.SharedSettings;
 import org.eclipse.lsp4j.ExecuteCommandParams;
 import org.eclipse.lsp4j.jsonrpc.CancelChecker;
 
@@ -37,13 +38,14 @@ public interface IDelegateCommandHandler {
 		 * Executes a command
 		 * 
 		 * @param params        command execution parameters
+		 * @param sharedSettings the shared settings.
 		 * @param cancelChecker check if cancel has been requested
 		 * @return the result of the command
 		 * @throws Exception the unhandled exception will be wrapped in
 		 *                   <code>org.eclipse.lsp4j.jsonrpc.ResponseErrorException</code>
 		 *                   and be wired back to the JSON-RPC protocol caller
 		 */
-		Object executeCommand(ExecuteCommandParams params, CancelChecker cancelChecker) throws Exception;
+		Object executeCommand(ExecuteCommandParams params, SharedSettings sharedSettings, CancelChecker cancelChecker) throws Exception;
 	}
 
 	/**
diff --git a/org.eclipse.lemminx/src/test/java/org/eclipse/lemminx/MockXMLLanguageServer.java b/org.eclipse.lemminx/src/test/java/org/eclipse/lemminx/MockXMLLanguageServer.java
index 5196ad64d0..e5118c1645 100644
--- a/org.eclipse.lemminx/src/test/java/org/eclipse/lemminx/MockXMLLanguageServer.java
+++ b/org.eclipse.lemminx/src/test/java/org/eclipse/lemminx/MockXMLLanguageServer.java
@@ -17,9 +17,12 @@
 
 import org.eclipse.lemminx.customservice.ActionableNotification;
 import org.eclipse.lemminx.services.extensions.commands.IXMLCommandService.IDelegateCommandHandler;
+import org.eclipse.lsp4j.DidOpenTextDocumentParams;
 import org.eclipse.lsp4j.ExecuteCommandParams;
 import org.eclipse.lsp4j.MessageParams;
 import org.eclipse.lsp4j.PublishDiagnosticsParams;
+import org.eclipse.lsp4j.TextDocumentIdentifier;
+import org.eclipse.lsp4j.TextDocumentItem;
 
 /**
  * Mock XML Language server which helps to track show messages, actionable
@@ -65,4 +68,11 @@ public CompletableFuture<Object> executeCommand(String command, Object... argume
 		return getWorkspaceService().executeCommand(params);
 	}
 
+	public TextDocumentIdentifier didOpen(String fileURI, String xml) {
+		TextDocumentIdentifier xmlIdentifier = new TextDocumentIdentifier(fileURI);
+		DidOpenTextDocumentParams params = new DidOpenTextDocumentParams(
+				new TextDocumentItem(xmlIdentifier.getUri(), "xml", 1, xml));
+		getTextDocumentService().didOpen(params);
+		return xmlIdentifier;
+	}
 }
diff --git a/org.eclipse.lemminx/src/test/java/org/eclipse/lemminx/XMLAssert.java b/org.eclipse.lemminx/src/test/java/org/eclipse/lemminx/XMLAssert.java
index 1dcdc7a932..6f38e9da95 100644
--- a/org.eclipse.lemminx/src/test/java/org/eclipse/lemminx/XMLAssert.java
+++ b/org.eclipse.lemminx/src/test/java/org/eclipse/lemminx/XMLAssert.java
@@ -18,7 +18,6 @@
 import static org.junit.jupiter.api.Assertions.assertNotEquals;
 import static org.junit.jupiter.api.Assertions.assertNotNull;
 import static org.junit.jupiter.api.Assertions.assertNull;
-import static org.junit.jupiter.api.Assertions.assertNotNull;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 
 import java.nio.file.Path;
@@ -94,7 +93,7 @@
 import org.junit.jupiter.api.Assertions;
 
 /**
- * XML
+ * XML Assert
  *
  */
 public class XMLAssert {
@@ -123,7 +122,8 @@ public class XMLAssert {
 
 	private static final String FILE_URI = "test.xml";
 
-	private static final CancelChecker NULL_CHECKER = () -> {};
+	private static final CancelChecker NULL_CHECKER = () -> {
+	};
 
 	public static class SettingsSaveContext extends AbstractSaveContext {
 
@@ -314,7 +314,8 @@ public static void testTagCompletion(String value, String expected) throws BadLo
 		testTagCompletion(value, expected, new SharedSettings());
 	}
 
-	public static void testTagCompletion(String value, String expected, SharedSettings settings) throws BadLocationException {
+	public static void testTagCompletion(String value, String expected, SharedSettings settings)
+			throws BadLocationException {
 		int offset = value.indexOf('|');
 		value = value.substring(0, offset) + value.substring(offset + 1);
 
@@ -333,7 +334,8 @@ public static void testTagCompletion(String value, String expected, SharedSettin
 		assertEquals(expected, actual);
 	}
 
-	public static void testTagCompletion(String value, AutoCloseTagResponse expected, SharedSettings settings) throws BadLocationException {
+	public static void testTagCompletion(String value, AutoCloseTagResponse expected, SharedSettings settings)
+			throws BadLocationException {
 		int offset = value.indexOf('|');
 		value = value.substring(0, offset) + value.substring(offset + 1);
 
@@ -628,15 +630,17 @@ public static CodeAction ca(Diagnostic d, TextEdit... te) {
 		codeAction.setTitle("");
 		codeAction.setDiagnostics(Arrays.asList(d));
 
-		VersionedTextDocumentIdentifier versionedTextDocumentIdentifier = new VersionedTextDocumentIdentifier(FILE_URI,
-				0);
-
-		TextDocumentEdit textDocumentEdit = new TextDocumentEdit(versionedTextDocumentIdentifier, Arrays.asList(te));
+		TextDocumentEdit textDocumentEdit = tde(FILE_URI, te);
 		WorkspaceEdit workspaceEdit = new WorkspaceEdit(Collections.singletonList(Either.forLeft(textDocumentEdit)));
 		codeAction.setEdit(workspaceEdit);
 		return codeAction;
 	}
 
+	public static TextDocumentEdit tde(String uri, TextEdit... te) {
+		VersionedTextDocumentIdentifier versionedTextDocumentIdentifier = new VersionedTextDocumentIdentifier(uri, 1);
+		return new TextDocumentEdit(versionedTextDocumentIdentifier, Arrays.asList(te));
+	}
+
 	public static CodeAction ca(Diagnostic d, Either<TextDocumentEdit, ResourceOperation>... ops) {
 		CodeAction codeAction = new CodeAction();
 		codeAction.setDiagnostics(Collections.singletonList(d));
@@ -1325,7 +1329,8 @@ public static void testSelectionRange(String xml, SelectionRange... selectionRan
 			stringBuilder.deleteCharAt(nextPipe);
 			nextPipe = stringBuilder.indexOf("|");
 		}
-		assertEquals(selectionRanges.length, cursorOffsets.size(), "Number of cursors and SelectionRanges should be equal");
+		assertEquals(selectionRanges.length, cursorOffsets.size(),
+				"Number of cursors and SelectionRanges should be equal");
 		testSelectionRange(stringBuilder.toString(), cursorOffsets, selectionRanges);
 	}
 
diff --git a/org.eclipse.lemminx/src/test/java/org/eclipse/lemminx/extensions/contentmodel/commands/AssociateGrammarCommandTest.java b/org.eclipse.lemminx/src/test/java/org/eclipse/lemminx/extensions/contentmodel/commands/AssociateGrammarCommandTest.java
new file mode 100644
index 0000000000..511c98ce34
--- /dev/null
+++ b/org.eclipse.lemminx/src/test/java/org/eclipse/lemminx/extensions/contentmodel/commands/AssociateGrammarCommandTest.java
@@ -0,0 +1,124 @@
+/*******************************************************************************
+* Copyright (c) 2021 Red Hat Inc. and others.
+* All rights reserved. This program and the accompanying materials
+* which accompanies this distribution, and is available at
+* http://www.eclipse.org/legal/epl-v20.html
+*
+* SPDX-License-Identifier: EPL-2.0
+*
+* Contributors:
+*     Red Hat Inc. - initial API and implementation
+*******************************************************************************/
+package org.eclipse.lemminx.extensions.contentmodel.commands;
+
+import static org.eclipse.lemminx.XMLAssert.tde;
+import static org.eclipse.lemminx.XMLAssert.te;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+
+import java.io.File;
+import java.util.concurrent.ExecutionException;
+
+import org.eclipse.lemminx.MockXMLLanguageServer;
+import org.eclipse.lemminx.extensions.contentmodel.commands.AssociateGrammarCommand.GrammarBindingType;
+import org.eclipse.lemminx.utils.platform.Platform;
+import org.eclipse.lsp4j.TextDocumentEdit;
+import org.eclipse.lsp4j.TextDocumentIdentifier;
+import org.junit.jupiter.api.Test;
+
+/**
+ * Test for associating a grammar to a given XML command.
+ * 
+ * @author Angelo ZERR
+ *
+ */
+public class AssociateGrammarCommandTest {
+
+	@Test
+	public void associateWithXSDNoNamespaceShemaLocation() throws InterruptedException, ExecutionException {
+		MockXMLLanguageServer languageServer = new MockXMLLanguageServer();
+
+		String xml = "<?xml version=\"1.0\" ?>\r\n" + //
+				"<foo/>";
+		String xmlPath = getFileURI("src/test/resources/tag.xml");
+		TextDocumentIdentifier xmlIdentifier = languageServer.didOpen(xmlPath, xml);
+		String xsdPath = getFileURI("src/test/resources/xsd/tag.xsd");
+		String bindingType = GrammarBindingType.XSD.getName();
+
+		TextDocumentEdit actual = (TextDocumentEdit) languageServer
+				.executeCommand(AssociateGrammarCommand.COMMAND_ID, xmlIdentifier, xsdPath, bindingType).get();
+		assertNotNull(actual);
+
+		assertEquals(actual, tde(xmlPath, te(1, 4, 1, 4, //
+				" xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\"\r\n" + //
+						" xsi:noNamespaceSchemaLocation=\"xsd/tag.xsd\"")));
+	}
+
+	@Test
+	public void associateWithXSDSchemaLocation() throws Exception {
+		MockXMLLanguageServer languageServer = new MockXMLLanguageServer();
+
+		String xml = "<?xml version=\"1.0\" ?>\r\n" + //
+				"<foo/>";
+		String xmlPath = getFileURI("src/test/resources/tag.xml");
+		TextDocumentIdentifier xmlIdentifier = languageServer.didOpen(xmlPath, xml);
+
+		String xsdPath = getFileURI("src/test/resources/xsd/team.xsd");
+		String bindingType = GrammarBindingType.XSD.getName();
+
+		TextDocumentEdit actual = (TextDocumentEdit) languageServer
+				.executeCommand(AssociateGrammarCommand.COMMAND_ID, xmlIdentifier, xsdPath, bindingType).get();
+		assertNotNull(actual);
+
+		assertEquals(actual, tde(xmlPath, te(1, 4, 1, 4, //
+				" xmlns=\"team_namespace\"\r\n" + //
+						" xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\"\r\n" + //
+						" xsi:schemaLocation=\"team_namespace xsd/team.xsd\"")));
+	}
+
+	@Test
+	public void associateWithDTD() throws InterruptedException, ExecutionException {
+		MockXMLLanguageServer languageServer = new MockXMLLanguageServer();
+
+		String xml = "<?xml version=\"1.0\" ?>\r\n" + //
+				"<foo/>";
+		String xmlPath = getFileURI("src/test/resources/tag.xml");
+		TextDocumentIdentifier xmlIdentifier = languageServer.didOpen(xmlPath, xml);
+		String dtdPath = getFileURI("src/test/resources/dtd/tag.dtd");
+		String bindingType = GrammarBindingType.DTD.getName();
+
+		TextDocumentEdit actual = (TextDocumentEdit) languageServer
+				.executeCommand(AssociateGrammarCommand.COMMAND_ID, xmlIdentifier, dtdPath, bindingType).get();
+		assertNotNull(actual);
+
+		assertEquals(actual, tde(xmlPath, te(1, 0, 1, 0, //
+				"<!DOCTYPE foo SYSTEM \"dtd/tag.dtd\">\r\n")));
+	}
+
+	@Test
+	public void associateWithXMLModel() throws InterruptedException, ExecutionException {
+		MockXMLLanguageServer languageServer = new MockXMLLanguageServer();
+
+		String xml = "<?xml version=\"1.0\" ?>\r\n" + //
+				"<foo/>";
+		String xmlPath = getFileURI("src/test/resources/tag.xml");
+		TextDocumentIdentifier xmlIdentifier = languageServer.didOpen(xmlPath, xml);
+		String dtdPath = getFileURI("src/test/resources/dtd/tag.dtd");
+		String bindingType = GrammarBindingType.XML_MODEL.getName();
+
+		TextDocumentEdit actual = (TextDocumentEdit) languageServer
+				.executeCommand(AssociateGrammarCommand.COMMAND_ID, xmlIdentifier, dtdPath, bindingType).get();
+		assertNotNull(actual);
+
+		assertEquals(actual, tde(xmlPath, te(1, 0, 1, 0, //
+				"<?xml-model href=\"dtd/tag.dtd\"?>\r\n")));
+	}
+
+	private static String getFileURI(String fileName) {
+		String uri = new File(fileName).toURI().toString();
+		if (Platform.isWindows && !uri.startsWith("file://")) {
+			uri = uri.replace("file:/", "file:///");
+		}
+		return uri;
+	}
+}
diff --git a/org.eclipse.lemminx/src/test/java/org/eclipse/lemminx/extensions/contentmodel/commands/XMLValidationCommandTest.java b/org.eclipse.lemminx/src/test/java/org/eclipse/lemminx/extensions/contentmodel/commands/XMLValidationCommandTest.java
index db87a4953f..3bf8cd6aaf 100644
--- a/org.eclipse.lemminx/src/test/java/org/eclipse/lemminx/extensions/contentmodel/commands/XMLValidationCommandTest.java
+++ b/org.eclipse.lemminx/src/test/java/org/eclipse/lemminx/extensions/contentmodel/commands/XMLValidationCommandTest.java
@@ -32,11 +32,9 @@
 import org.eclipse.lsp4j.CompletionList;
 import org.eclipse.lsp4j.CompletionParams;
 import org.eclipse.lsp4j.DiagnosticSeverity;
-import org.eclipse.lsp4j.DidOpenTextDocumentParams;
 import org.eclipse.lsp4j.Position;
 import org.eclipse.lsp4j.PublishDiagnosticsParams;
 import org.eclipse.lsp4j.TextDocumentIdentifier;
-import org.eclipse.lsp4j.TextDocumentItem;
 import org.eclipse.lsp4j.jsonrpc.messages.Either;
 import org.junit.jupiter.api.Test;
 
@@ -83,7 +81,7 @@ public void validationFileCommand() throws Exception {
 					"</root>";
 
 			// Open the XML document, the validation is triggered asynchronously
-			TextDocumentIdentifier xmlIdentifier = didOpen(languageServer, "test.xml", xml);
+			TextDocumentIdentifier xmlIdentifier = languageServer.didOpen("test.xml", xml);
 
 			// Wait for:
 			// - downloading of XSD from the HTTP server to lemminx cache
@@ -209,7 +207,7 @@ public void validationAllFilesCommand() throws Exception {
 					"</root>";
 
 			// Open the XML document, the validation is triggered asynchronously
-			TextDocumentIdentifier xml1Identifier = didOpen(languageServer, "test1.xml", xml1);
+			TextDocumentIdentifier xml1Identifier = languageServer.didOpen("test1.xml", xml1);
 
 			// Wait for to collect diagnostics in the proper order (XSD diagnostics followed
 			// by DTD diagnostics)
@@ -223,7 +221,7 @@ public void validationAllFilesCommand() throws Exception {
 					"</root>";
 
 			// Open the XML document, the validation is triggered asynchronously
-			TextDocumentIdentifier xml2Identifier = didOpen(languageServer, "test2.xml", xml2);
+			TextDocumentIdentifier xml2Identifier = languageServer.didOpen("test2.xml", xml2);
 
 			// Wait for:
 			// - downloading of XSD from the HTTP server to lemminx cache
@@ -331,14 +329,6 @@ public void validationAllFilesCommand() throws Exception {
 		}
 	}
 
-	private static TextDocumentIdentifier didOpen(MockXMLLanguageServer languageServer, String fileURI, String xml) {
-		TextDocumentIdentifier xmlIdentifier = new TextDocumentIdentifier(fileURI);
-		DidOpenTextDocumentParams params = new DidOpenTextDocumentParams(
-				new TextDocumentItem(xmlIdentifier.getUri(), "xml", 1, xml));
-		languageServer.getTextDocumentService().didOpen(params);
-		return xmlIdentifier;
-	}
-
 	private static CompletionList completion(MockXMLLanguageServer languageServer, TextDocumentIdentifier xmlIdentifier)
 			throws BadLocationException, InterruptedException, ExecutionException {
 		DOMDocument document = languageServer.getDocument(xmlIdentifier.getUri());
diff --git a/org.eclipse.lemminx/src/test/java/org/eclipse/lemminx/services/extensions/commands/CommandServiceTest.java b/org.eclipse.lemminx/src/test/java/org/eclipse/lemminx/services/extensions/commands/CommandServiceTest.java
index 14fe5d13bb..fa9dea9997 100644
--- a/org.eclipse.lemminx/src/test/java/org/eclipse/lemminx/services/extensions/commands/CommandServiceTest.java
+++ b/org.eclipse.lemminx/src/test/java/org/eclipse/lemminx/services/extensions/commands/CommandServiceTest.java
@@ -36,7 +36,7 @@ public CommandServiceTest() {
 	}
 
 	private void registerCommand(String command) {
-		languageServer.registerCommand(command, (params, cancelChecker) -> {
+		languageServer.registerCommand(command, (params, sharedSettings, cancelChecker) -> {
 			return params.getCommand() + (params.getArguments().isEmpty() ? ""
 					: ": " + params.getArguments().stream().map(a -> a.toString()).collect(Collectors.joining(" ")));
 		});