Sorry. Left out a couple of critical bits of information. I'm selecting two columns and ordering by one of them - but trying to get the CS string for the second column, against the first column... both columns are integers, and the second column has repeated values but I need the distinct list... and of course if distinct is used, the exact expression must appear in the order by list.

However, because I've got to cast it as a varchar to concatenate the comma, I can only order by the cast as varchar - which doesn't give the correct integer sorting...

...does that make more sense now?