The patterns of social integration of adults with primary and secondary groups were evaluated for 196 adult cleft subjects, their 190 siblings and 209 random controls. Results indicated that cleft adults tended to rely on the extended family for mutual aid and social activities. They also participated less frequently in voluntary associations and relied on a few one-to-one friendships. Social activities tended to be that of informal visiting patterns. While it would be inaccurate to characterize the cleft adult family as grossly different from other American families, they are a definable population experiencing some degree of limitation associated with having a cleft.