>In a multiuser environment, it is difficult to use PACK to remove a deleted record. To work around this problem, we can recycle the deleted records. In that case, we do not need to physically remove those deleted records. But in VFP if the table has primary index the deleted records will have a problem with the "uniqueness". I wonder whether there is a simple way to work around it.

Sure. Change the key when you delete a record. Depending on how you generate unique keys, you can set a rule to have unique "real" keys and unique "deleted" keys.

Vlad