diff --git a/src/_utils.js b/src/_utils.js
index dcbffeed..91991ad0 100644
--- a/src/_utils.js
+++ b/src/_utils.js
@@ -190,12 +190,20 @@ export const validateExpression = (expr, scope) => (
   expr.traverse(validateExpressionVisitor, scope)
 )
 
-export const getExternalReference = (path, imports) => {
+export const getExternalReference = (path, {imports, requires}) => {
   const {node} = path
   if (!t.isIdentifier(node)) {
     return null
   }
 
+  const requireExpr = requires.filter(path => (
+    path.get('id').node.name === node.name
+  ))[0]
+
+  if (requireExpr) {
+    return requireExpr.get('init').get('arguments')[0].node.value
+  }
+
   const importExpr = imports.filter(path => {
     const specifiers = path.get('specifiers')
     if (specifiers.length !== 1) {
@@ -230,15 +238,15 @@ export const generateAttribute = (name, value) => (
   )
 )
 
-export const isValidCss = (str) => {
+export const isValidCss = str => {
   try {
     parseCss(str)
     return true
-  } catch (e) {}
+  } catch (err) {}
   return false
 }
 
-export const makeSourceMapGenerator = (file) => {
+export const makeSourceMapGenerator = file => {
   const filename = file.opts.sourceFileName
   const generator = new SourceMapGenerator({
     file: filename,
diff --git a/src/babel-external.js b/src/babel-external.js
index 2954be55..7d2c3d2a 100644
--- a/src/babel-external.js
+++ b/src/babel-external.js
@@ -6,26 +6,24 @@ import {
   getExpressionText,
   restoreExpressions,
   makeStyledJsxCss,
-  globalCss,
   isValidCss,
   makeSourceMapGenerator,
   addSourceMaps
 } from './_utils'
 
-export const exportDefaultDeclarationVisitor = ({
-  path: entryPath,
+const visitor = ({
+  path,
   styleId,
   types: t,
   validate = false,
   state
 }) => {
-  const path = entryPath.get('declaration')
   if (!path.isTemplateLiteral() || path.isStringLiteral()) {
     return
   }
   const css = getExpressionText(path)
   const prefix = `[${MARKUP_ATTRIBUTE_EXTERNAL}~="${styleId}"]`
-  const isTemplateLiteral = css.modified
+  const isTemplateLiteral = Boolean(css.modified)
   const useSourceMaps = Boolean(state.file.opts.sourceMaps)
 
   let globalCss = css.modified || css
@@ -54,7 +52,7 @@ export const exportDefaultDeclarationVisitor = ({
       filename
     )
   } else {
-    localCss = localCss = transform(
+    localCss = transform(
       prefix,
       css.modified || css
     )
@@ -85,6 +83,20 @@ export const exportDefaultDeclarationVisitor = ({
   )
 }
 
+export const exportDefaultDeclarationVisitor = ({path, ...rest}) => (
+  visitor({
+    path: path.get('declaration'),
+    ...rest
+  })
+)
+
+export const moduleExportsVisitor = ({path, ...rest}) => (
+  visitor({
+    path: path.get('right'),
+    ...rest
+  })
+)
+
 export default function ({types}) {
   return {
     visitor: {
@@ -95,6 +107,17 @@ export default function ({types}) {
           types,
           state
         })
+      },
+      AssignmentExpression(path, state) {
+        if (path.get('left').getSource() !== 'module.exports') {
+          return
+        }
+        moduleExportsVisitor({
+          path,
+          styleId: hash(state.file.opts.filename),
+          types,
+          state
+        })
       }
     }
   }
diff --git a/src/babel.js b/src/babel.js
index 9a58a0f0..fab1879a 100644
--- a/src/babel.js
+++ b/src/babel.js
@@ -4,7 +4,10 @@ import hash from 'string-hash'
 
 // Ours
 import transform from '../lib/style-transform'
-import {exportDefaultDeclarationVisitor} from './babel-external'
+import {
+  exportDefaultDeclarationVisitor,
+  moduleExportsVisitor
+} from './babel-external'
 
 import {
   isGlobalEl,
@@ -34,7 +37,17 @@ export default function ({types: t}) {
     inherits: jsx,
     visitor: {
       ImportDeclaration(path, state) {
-        state.imports = (state.imports || []).concat(path)
+        state.imports = (state.imports || []).concat([path])
+      },
+      VariableDeclarator(path, state) {
+        const subpath = path.get('init')
+        if (
+          !subpath.isCallExpression() ||
+          subpath.get('callee').node.name !== 'require'
+        ) {
+          return
+        }
+        state.requires = (state.requires || []).concat([path])
       },
       JSXOpeningElement(path, state) {
         const el = path.node
@@ -132,7 +145,10 @@ export default function ({types: t}) {
             const expression = child.get('expression')
 
             if (t.isIdentifier(expression)) {
-              let externalSourcePath = getExternalReference(expression, state.imports)
+              let externalSourcePath = getExternalReference(expression, {
+                imports: state.imports,
+                requires: state.requires
+              })
               if (externalSourcePath) {
                 externalSourcePath = resolvePath(externalSourcePath, state.file.opts.filename)
                 state.externalStyles.push([
@@ -299,6 +315,19 @@ export default function ({types: t}) {
           validate: true,
           state
         })
+      },
+      AssignmentExpression(path, state) {
+        if (path.get('left').getSource() !== 'module.exports') {
+          return
+        }
+        const filename = state.file.opts.filename
+        moduleExportsVisitor({
+          path,
+          styleId: hash(filename),
+          types: t,
+          validate: true,
+          state
+        })
       }
     }
   }
diff --git a/test/external.js b/test/external.js
index c59b5790..1f51581d 100644
--- a/test/external.js
+++ b/test/external.js
@@ -16,8 +16,14 @@ const transform = (file, opts = {}) => (
 test('transpiles external stylesheets', async t => {
   const {code} = await transform(
     './fixtures/styles.js',
-    { sourceMaps: true }
+    {sourceMaps: true}
   )
   const out = await read('./fixtures/styles.out.js')
   t.is(code, out.trim())
 })
+
+test('transpiles external stylesheets (CommonJS modules)', async t => {
+  const {code} = await transform('./fixtures/styles2.js')
+  const out = await read('./fixtures/styles2.out.js')
+  t.is(code, out.trim())
+})
diff --git a/test/fixtures/external-stylesheet.js b/test/fixtures/external-stylesheet.js
index 5f4664fd..02bf71bd 100644
--- a/test/fixtures/external-stylesheet.js
+++ b/test/fixtures/external-stylesheet.js
@@ -1,5 +1,5 @@
 import styles from './styles'
-import styles2 from './styles2'
+const styles2 = require('./styles2')
 
 export default () => (
   <div>
diff --git a/test/fixtures/external-stylesheet.out.js b/test/fixtures/external-stylesheet.out.js
index beb40e1b..edc38151 100644
--- a/test/fixtures/external-stylesheet.out.js
+++ b/test/fixtures/external-stylesheet.out.js
@@ -1,6 +1,6 @@
 import _JSXStyle from 'styled-jsx/style';
 import styles from './styles';
-import styles2 from './styles2';
+const styles2 = require('./styles2');
 
 export default (() => <div data-jsx={1144769207} data-jsx-ext={"626947301"}>
     <p data-jsx={1144769207} data-jsx-ext={"626947301"}>test</p>
diff --git a/test/fixtures/styles2.js b/test/fixtures/styles2.js
index 3a6ca0f8..36d75aa2 100644
--- a/test/fixtures/styles2.js
+++ b/test/fixtures/styles2.js
@@ -1,3 +1,3 @@
-export default `
+module.exports = `
   div { font-size: 3em }
 `