 <p>Have a look at the <a href="http://www.codeplex.com/AppArchGuide" rel="nofollow noreferrer">patterns &amp; practices Application Architecture Guide 2.0 (Beta 2 Release)</a> on Codeplex. The <a href="http://msdn.microsoft.com/en-us/practices/default.aspx" rel="nofollow noreferrer">patterns &amp; practices division of Microsoft</a> also has guidelines for naming etc.</p>