This study examined the influences of mothers' involvement in their children's social lives. Subjects were 143 children in grades 3 through 6 in two schools in the Kitchener-Waterloo region of Ontario and their mothers. Information on children's social behavior was obtained from peer ratings on the Revised Class Play test. Mothers completed questionnaires assessing their own peer group experiences in childhood and currently; their affective reactions to peer experiences; the value they placed on sociability and obedience; and their beliefs about their children's social behavior. Mothers also completed a checklist assessing their involvement in their children's lives. Four principal types of activities characterized mothers' involvement. These were Monitoring, Orchestration, Advice and Support, and High-Concern activities. Mothers tended to perceive their children as having the same level of sociability as they viewed themselves as having. Mothers who valued sociability tended to perceive their children's social behavior similarly to the way peers did. Results of the maternal involvement assessment included: (1) mothers who were socially withdrawn in childhood or sociable as adults had higher orchestration scores; (2) maternal involvement was greater when mothers perceived their children to be withdrawn; and (3) the more concerned mothers were, the greater were their advice and support and high-concern scores. A reference list of 15 items is included. (BC)