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    <p>You can't do it this way. First, lambda expressions can be converted only to delegate types or <code>Expression&lt;T&gt;</code>.</p> <p>If you change the signature of the method (for now ignoring its implementation) to <code>public void RunAndRaise(Expression&lt;Action&gt; Exp)</code>, the compiler complains that “An expression tree may not contain an assignment operator”. </p> <p>You could do it by specifying the property using lambda and the value you want to set it to in another parameter. <s>Also, I didn't figure out a way to access the value of <code>vm</code> from the expression, so you have to put that in another parameter (you can't use <code>this</code> for that, because you need the proper inherited type in the expression)</s>:<sup>see edit</sup></p> <pre><code>public static void SetAndRaise&lt;TViewModel, TProperty&gt;( TViewModel vm, Expression&lt;Func&lt;TViewModel, TProperty&gt;&gt; exp, TProperty value) where TViewModel : ViewModelBase { var propertyInfo = (PropertyInfo)((MemberExpression)exp.Body).Member; propertyInfo.SetValue(vm, value, null); vm.PropertyChanged(propertyInfo.Name); } </code></pre> <p>Another possibility (and one I like more) is to raise the event from setter specifically using lambda like this:</p> <pre><code>private int m_value; public int Value { get { return m_value; } set { m_value = value; RaisePropertyChanged(this, vm =&gt; vm.Value); } } static void RaisePropertyChanged&lt;TViewModel, TProperty&gt;( TViewModel vm, Expression&lt;Func&lt;TViewModel, TProperty&gt;&gt; exp) where TViewModel : ViewModelBase { var propertyInfo = (PropertyInfo)((MemberExpression)exp.Body).Member; vm.PropertyChanged(propertyInfo.Name); } </code></pre> <p>This way, you can use the properties as usual, and you could also raise events for computed properties, if you had them.</p> <p><strong>EDIT:</strong> While reading through <a href="http://blogs.msdn.com/b/mattwar/archive/2008/11/18/linq-links.aspx" rel="nofollow">Matt Warren's series about implementing <code>IQueryable&lt;T&gt;</code></a>, I realized I can access the referenced value, which simplifies the usage of <code>RaisePropertyChanged()</code> (although it won't help much with your <code>SetAndRaise()</code>):</p> <pre><code>private int m_value; public int Value { get { return m_value; } set { m_value = value; RaisePropertyChanged(() =&gt; Value); } } static void RaisePropertyChanged&lt;TProperty&gt;(Expression&lt;Func&lt;TProperty&gt;&gt; exp) { var body = (MemberExpression)exp.Body; var propertyInfo = (PropertyInfo)body.Member; var vm = (ViewModelBase)((ConstantExpression)body.Expression).Value; vm.PropertyChanged(vm, new PropertyChangedEventArgs(propertyInfo.Name)); } </code></pre>
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    1. CO+1 for a more complete answer.
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    2. COalready +1ed, and now accept - thank you for the great answer
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    3. CObtw - regarding your second answer, avoiding bulky code like that is what I was trying to avoid in the first place. I took your answer and made it into an extension method, which should let me set aotu-properties and have the propertyChanged event get raised automatically. Thanks again.
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