http://blogs.msdn.com/b/jamesnewkirk/archive/2005/02/20/377160.aspxIn a previous post I wrote about changing the interface that the Bookmarks class would implement from IDictionary to ICollection&lt;Bookmark&gt;. In order to do this I want to look at the test list and see if there are any new tests or tests that we haden-USTelligent Evolution Platform Developer Build (Build: 5.6.50428.7875)http://blogs.msdn.com/b/jamesnewkirk/archive/2005/02/20/377160.aspx#377556Mon, 21 Feb 2005 20:30:00 GMT91d46819-8472-40ad-a661-2c78acb4018c:377556Tim Shakarian&quot;A note to self; next time I implement a class that inherits from an interface I need to make sure the class implements the interface right from the start and just have each unimplemented method throw an exception. &quot; <br> <br>This is a very good practice. I would recommend throwing a NotImplementedException for clarity.<div style="clear:both;"></div><img src="http://blogs.msdn.com/aggbug.aspx?PostID=377556" width="1" height="1">