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    <p>I discovered that you need the original way from MSDN if you have multiple controls that invoke the same commands, otherwise each control will new its own RelayCommand. I didn't realize this because my app only has one control per command.</p> <p>So to simplify the code in ViewModels, I'll create a command wrapper class that stores (and lazily instantiates) all the RelayCommands and throw it in my ViewModelBase class. This way users do not have to directly instantiate RelayCommand or DelegateCommand objects and don't need to know anything about them:</p> <pre><code> /// &lt;summary&gt; /// Wrapper for command objects, created for convenience to simplify ViewModel code /// &lt;/summary&gt; /// &lt;author&gt;Ben Schoepke&lt;/author&gt; public class CommandWrapper { private readonly List&lt;DelegateCommand&lt;object&gt;&gt; _commands; // cache all commands as needed /// &lt;summary&gt; /// &lt;/summary&gt; public CommandWrapper() { _commands = new List&lt;DelegateCommand&lt;object&gt;&gt;(); } /// &lt;summary&gt; /// Returns the ICommand object that contains the given delegates /// &lt;/summary&gt; /// &lt;param name="executeMethod"&gt;Defines the method to be called when the command is invoked&lt;/param&gt; /// &lt;param name="canExecuteMethod"&gt;Defines the method that determines whether the command can execute in its current state. /// Pass null if the command should always be executed.&lt;/param&gt; /// &lt;returns&gt;The ICommand object that contains the given delegates&lt;/returns&gt; /// &lt;author&gt;Ben Schoepke&lt;/author&gt; public ICommand GetCommand(Action&lt;object&gt; executeMethod, Predicate&lt;object&gt; canExecuteMethod) { // Search for command in list of commands var command = (_commands.Where( cachedCommand =&gt; cachedCommand.ExecuteMethod.Equals(executeMethod) &amp;&amp; cachedCommand.CanExecuteMethod.Equals(canExecuteMethod))) .FirstOrDefault(); // If command is found, return it if (command != null) { return command; } // If command is not found, add it to the list command = new DelegateCommand&lt;object&gt;(executeMethod, canExecuteMethod); _commands.Add(command); return command; } } </code></pre> <p>This class is also lazily instantiated by the ViewModelBase class, so ViewModels that do not have any commands will avoid the extra allocations.</p>
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    1. COIf you are really that worried about your memory usage, wouldn't it make sense to only instantiate commands that you are going to use? For example, if you have a VM that exposes 3 commands, and only one is ever used, just drop the rest. If you are using all of your VM commands (which you should be), then your system of lazy loading will use MORE memory and MORE processor time which defeats the purpose of optimizing in the first place, especially for embedded systems.
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