>Have you visually inspected the data itself? We had a problem similar to that and it turned out we had 'garbage' in a couple of fields.

I failed to mention that, but yes, I did look at it and didn't see any problems. I even deleted all records in the table, renamed the .DBF and .CDX, and re-created a new, empty copy of the table. Since my post, I found that there are some data-driven conditions in my code under which the lockups do not occur, so I need to follow up on that. However, I still don't understand why LOCATE or SCAN would lock up, assuming that the data is "clean". Thanks for the response.