>>>That did it guys ( ordered it in the invoice loop )
>>
>>Pity (g) - I would love to have known why the OrderBy/GroupBy option didn't work.
>>Maybe Rob knows ?
>>
>> very strange though
>
>Not entirely sure, but if I had to guess, the grouping operation might be done in parallel, so the order may be lost when the results are recombined.

I thought Linq was sequential (unless you specifically use PLinq) but I could be wrong.

I came across this (which, of course, may not be correct): http://stackoverflow.com/questions/204505/preserving-order-with-linq

Snip : " GroupBy - The IGrouping objects are yielded in an order based on the order of the elements in source that produced the first key of each IGrouping. Elements in a grouping are yielded in the order they appear in source."

This was certainly the behaviour in my tests - i.e. invoice amounts were in the right order, clients ordered by descending largest invoice.