What types of problems are you expecting?

You shouldn't have any problems with simple examples like that. The only thing I would say is that if you have really big datasets with really long lists like that, then a join would be better and faster. But if it's just a couple of items, then that should work okay.

Alex I'm not sure how all the different SQL servers might deal with the syntax, since I haven't explored them yet.

Richard I'm not privy to the internals of SQL in Access (or the servers), and if that syntax, when it's compiled is more efficient than a whole bunch or ORs for a single field. So far, I have a maximum of 7 in the list, so that's less than the 9 (I think it was) by default. On my version of Access, it takes all the Criteria/ors and puts them in one or in the Criteria line, if I hack out all the extra parentheses (that I presume aren't really necessary since it works without them).

Again, for something that small, I don't think there's much of a difference.