I want to add a closing note to this successful endeavor. I finally received two lists of names (and their associated records)---I copied these two lists to a worksheet with a total of 10,381 records. When I did the run (which took less than a minute) I got some surprising (but correct ) results---there were dupicates in the first list (unexpected) but no duplicates between the lists (also unexpected). Thanks HalfAce for providing the code which made this possible, and thanks also to Anne, Erik, and Chearn for your helpful suggestions---warm regards, Marion