Actually, GCLisp handles atoms in alists by ignoring them, whether they are strings, NIL, or other symbols. E.g., (SETQ abc '(c (c . 3) NIL (NIL . 4))) (ASSOC 'c abc) --> (c . 3) (ASSOC nil abc) --> (NIL . 4) This is in accordance with CLtL, I believe. David Loewenstern Naval Air Development Center code 7013 Warminster, PA 18974-5000 <dml@nadc.arpa>