Hi Jon, > 41 my $idterm = join('',"Q",$identifier); This is a syntax error. The "." form is fine or even: my $idterm = "Q$identifier"; > 43 $db->replace_document($idterm, $doc); I think you want: $db->replace_document_by_term($idterm, $doc); replace_document takes an id which is why you are getting the "isn't numeric" error. Rob