title: Where did System.Design go?
body: <p>I am making a C# project in which I am using ScintillaNet, and it says:</p>
  
  <blockquote>
    <p>The referenced assembly "ScintillaNet" could not be resolved because it has a dependency on "System.Design, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" which is not in the currently targeted framework ".NETFramework,Version=v4.0,Profile=Client". Please remove references to assemblies not in the targeted framework or consider retargeting your project.</p>
  </blockquote>
  
  <p>I tried adding a reference to <code>System.Design</code>, but it doesn't exist in my list. Do I need to download it somewhere? I have Microsoft Visual Studio 10.</p>