 <p><a href="http://stackoverflow.com/questions/649444/testing-equality-of-arrays-in-c/792459#792459">@Allen's answer</a>:</p> <pre><code>bool equals = a.Intersect(b).Count() == a.Union(b).Count() </code></pre> <p>is about arrays but as far as <code>IEnumerable&lt;T&gt;</code> methods are used, it can be used for <code>Dictionary&lt;K,V&gt;</code> too.</p>