http://blogs.msdn.com/b/alexj/archive/2009/12/02/tip-47-how-fix-up-can-make-it-hard-to-change-relationships.aspxProblem: Take this code: Category oldCategory = ctx.Categories .Include("Products") .First(c =&gt; c.Name == "Drink"); Category newCategory = new Category {Name = "Beverage"}; foreach(Product product in oldCategory.Products) { newCategory.Productsen-USTelligent Evolution Platform Developer Build (Build: 5.6.50428.7875)http://blogs.msdn.com/b/alexj/archive/2009/12/02/tip-47-how-fix-up-can-make-it-hard-to-change-relationships.aspx#9932459Fri, 04 Dec 2009 12:14:38 GMT91d46819-8472-40ad-a661-2c78acb4018c:9932459Shimmy Weitzhandler<p>Richard, good idea, but Y not ToArray that also has these extensions, and takes a few bytes less than a list :)</p> <div style="clear:both;"></div><img src="http://blogs.msdn.com/aggbug.aspx?PostID=9932459" width="1" height="1">http://blogs.msdn.com/b/alexj/archive/2009/12/02/tip-47-how-fix-up-can-make-it-hard-to-change-relationships.aspx#9931512Wed, 02 Dec 2009 17:36:02 GMT91d46819-8472-40ad-a661-2c78acb4018c:9931512Richard<p>How about:</p> <p>oldCategory.Products.ToList().ForEach(newCategory.Products.Add);</p><div style="clear:both;"></div><img src="http://blogs.msdn.com/aggbug.aspx?PostID=9931512" width="1" height="1">