I have been a programmer for some years now but I am a newcomer to LINQ and C# so forgive me if my question sounds particularly stupid. I hope someone may be able to point me in the right direction. My task is to come up with the ability to form a dynamic multiple group by linq query within a c# script using a generic list as a source. For example, say I have a list containing multiple items with the following structure: FieldChar1 - character FieldChar2 - character FieldChar3 - character FieldNum1 - numeric FieldNum2 - numeric In a nutshell I want to be able to create a LINQ query that will sum FieldNum1 and FieldNum2 grouped by any one, two or all three of the FieldChar fields that will be decided at runtime depending on the users requirements as well as selecting the FieldChar fields in the same query. I have the dynamic.cs in my project which icludes a GroupByMany extension method but I have to admit I am really not sure how to put these to use. I am able to get the desired results if I use a query with hard-wired group by requests but not dynamically. Apologies for any erroneous nomenclature, I am new to this language but any advice would be most welcome. Many thanks Alex