The neural cell adhesion molecule (N-CAM) is believed to be a key regulator of adhesive events in the nervous system and skeletal muscle. The recent isolation of N-CAM cDNAs from different tissues has identified a high degree of diversity in primary amino acid sequence between different isoforms. In this article, we review these recent studies and discuss methods for unravelling the functional consequences of the generation of multiple N-CAM polypeptides using gene transfection approaches.