Hi Hilary, thanks for getting back. I want to build a string that has all of the selected field offices delimited by a running count, so something like this: Colorado Field Office1Kansas Field Office2Nebraska Field Office3. My Multiple-selection list box is named "Field Office", in the Advanced view of my fields it looks like a folder, with "Value" MSLB inside of it. This works to build a comma delimited list: eval(eval(Value, 'concat(., ", ")'), "..") and this works to provide me with a final count: count(Value[. != ""]) so I thought I could put the two together to get what I want, like this: eval(eval(Value, 'concat(., count(Value[. != ""]))'), "..") However, I get a message that the formula has errors. Lara