diff --git a/README.md b/README.md
index abf3f64..bb7b6e0 100644
--- a/README.md
+++ b/README.md
@@ -18,6 +18,8 @@ atom.packages.onDidActivatePackage (pack) ->
   if pack.name == 'ex-mode'
     Ex = pack.mainModule.provideEx()
     Ex.registerCommand 'z', -> console.log("Zzzzzz...")
+    # Register an alias - Now :W acts like :w
+    Ex.registerAlias 'W', 'w'
 ```
 
 See `lib/ex.coffee` for some examples commands. Contributions are very welcome!
diff --git a/lib/ex-mode.coffee b/lib/ex-mode.coffee
index 1a4979d..e3a15b2 100644
--- a/lib/ex-mode.coffee
+++ b/lib/ex-mode.coffee
@@ -30,6 +30,7 @@ module.exports = ExMode =
 
   provideEx: ->
     registerCommand: Ex.registerCommand.bind(Ex)
+    registerAlias: Ex.registerAlias.bind(Ex)
 
   consumeVim: (vim) ->
     @vim = vim
diff --git a/lib/ex.coffee b/lib/ex.coffee
index 995c6b2..ca0ca0e 100644
--- a/lib/ex.coffee
+++ b/lib/ex.coffee
@@ -106,6 +106,9 @@ class Ex
   @registerCommand: (name, func) =>
     @singleton()[name] = func
 
+  @registerAlias: (alias, name) =>
+    @singleton()[alias] = (args) => @singleton()[name](args)
+
   quit: ->
     atom.workspace.getActivePane().destroyActiveItem()
 
diff --git a/spec/ex-commands-spec.coffee b/spec/ex-commands-spec.coffee
index 89420f9..35bfd22 100644
--- a/spec/ex-commands-spec.coffee
+++ b/spec/ex-commands-spec.coffee
@@ -4,7 +4,8 @@ os = require 'os'
 uuid = require 'node-uuid'
 helpers = require './spec-helper'
 
-Ex = require('../lib/ex').singleton()
+ExClass = require('../lib/ex')
+Ex = ExClass.singleton()
 
 describe "the commands", ->
   [editor, editorElement, vimState, exState, dir, dir2] = []
@@ -732,3 +733,21 @@ describe "the commands", ->
         atom.commands.dispatch(editorElement, 'ex-mode:open')
         submitNormalModeInputText(':set nonumber')
         expect(atom.config.get('editor.showLineNumbers')).toBe(false)
+
+  describe "aliases", ->
+    it "calls the aliased function without arguments", ->
+      ExClass.registerAlias('W', 'w')
+      spyOn(Ex, 'write')
+      keydown(':')
+      submitNormalModeInputText('W')
+      expect(Ex.write).toHaveBeenCalled()
+
+    it "calls the aliased function with arguments", ->
+      ExClass.registerAlias('W', 'write')
+      spyOn(Ex, 'W').andCallThrough()
+      spyOn(Ex, 'write')
+      keydown(':')
+      submitNormalModeInputText('W')
+      WArgs = Ex.W.calls[0].args[0]
+      writeArgs = Ex.write.calls[0].args[0]
+      expect(WArgs).toBe writeArgs