diff --git a/lib/pdk/cli.rb b/lib/pdk/cli.rb
index 576a656d1..2157cb5c4 100644
--- a/lib/pdk/cli.rb
+++ b/lib/pdk/cli.rb
@@ -91,6 +91,7 @@ def self.full_interview_option(dsl)
   require 'pdk/cli/convert'
   require 'pdk/cli/new'
   require 'pdk/cli/test'
+  require 'pdk/cli/update'
   require 'pdk/cli/validate'
   require 'pdk/cli/module'
 
diff --git a/lib/pdk/cli/update.rb b/lib/pdk/cli/update.rb
new file mode 100644
index 000000000..f821f1fda
--- /dev/null
+++ b/lib/pdk/cli/update.rb
@@ -0,0 +1,29 @@
+require 'pdk/cli/util'
+
+module PDK::CLI
+  @update_cmd = @base_cmd.define_command do
+    name 'update'
+    usage _('update [options]')
+    summary _('Update a module that has been created by or converted for use by PDK.')
+
+    flag nil, :noop, _('Do not update the module, just output what would be done.')
+    flag nil, :force, _('Update the module automatically, with no prompts.')
+
+    be_hidden
+
+    run do |opts, _args, _cmd|
+      require 'pdk/module/update'
+
+      PDK::CLI::Util.ensure_in_module!(
+        message:   _('`pdk update` can only be run from inside a valid module directory.'),
+        log_level: :info,
+      )
+
+      if opts[:noop] && opts[:force]
+        raise PDK::CLI::ExitWithError, _('You can not specify --noop and --force when updating a module')
+      end
+
+      PDK::Module::Update.invoke(opts)
+    end
+  end
+end
diff --git a/lib/pdk/module/update.rb b/lib/pdk/module/update.rb
new file mode 100644
index 000000000..0991958d8
--- /dev/null
+++ b/lib/pdk/module/update.rb
@@ -0,0 +1,9 @@
+module PDK
+  module Module
+    class Update
+      def self.invoke(_opts = {})
+        # TODO: do some updatey things
+      end
+    end
+  end
+end
diff --git a/spec/unit/pdk/cli/update_spec.rb b/spec/unit/pdk/cli/update_spec.rb
new file mode 100644
index 000000000..b43e4bb04
--- /dev/null
+++ b/spec/unit/pdk/cli/update_spec.rb
@@ -0,0 +1,61 @@
+require 'spec_helper'
+
+describe 'PDK::CLI update' do
+  let(:help_text) { a_string_matching(%r{^USAGE\s+pdk update}m) }
+
+  context 'when not run from inside a module' do
+    include_context 'run outside module'
+
+    it 'exits with an error' do
+      expect(logger).to receive(:error).with(a_string_matching(%r{must be run from inside a valid module}))
+
+      expect {
+        PDK::CLI.run(%w[update])
+      }.to raise_error(SystemExit) { |error|
+        expect(error.status).not_to eq(0)
+      }
+    end
+  end
+
+  context 'when run from inside a module' do
+    before(:each) do
+      allow(PDK::Util).to receive(:module_root).and_return('/path/to/test/module')
+    end
+
+    context 'and provided no flags' do
+      it 'invokes the updater with no options' do
+        expect(PDK::Module::Update).to receive(:invoke).with({})
+
+        PDK::CLI.run(%w[update])
+      end
+    end
+
+    context 'and the --noop flag has been passed' do
+      it 'passes the noop option through to the updater' do
+        expect(PDK::Module::Update).to receive(:invoke).with(noop: true)
+
+        PDK::CLI.run(%w[update --noop])
+      end
+    end
+
+    context 'and the --force flag has been passed' do
+      it 'passes the force option through to the updater' do
+        expect(PDK::Module::Update).to receive(:invoke).with(force: true)
+
+        PDK::CLI.run(%w[update --force])
+      end
+    end
+
+    context 'and the --force and --noop flags have been passed' do
+      it 'exits with an error' do
+        expect(logger).to receive(:error).with(a_string_matching(%r{can not specify --noop and --force}i))
+
+        expect {
+          PDK::CLI.run(%w[update --noop --force])
+        }.to raise_error(SystemExit) { |error|
+          expect(error.status).not_to eq(0)
+        }
+      end
+    end
+  end
+end