To identify positive indicators of social competence in preschoolers, a four-stage study involving over 100 three-and four-year-olds was done to examine correlates oi the frequency, quality, and effectiveness of various types of initiated and respondent behavior which occurred in social interaction situations. It was found that the most effective discriminator of competence was the succcssfulness of child-child social influence attempts, and a measure of social competence based on this finding was developed. Social competence, defined and measured as social influence effectiveness, was positively related to cognitive competence in a variety of problem soiving situations, and to affective and cognitive perspective-taking ability. The results arc discussed with reference (o the concept of effectancc motivation.Eflbrts to evaluate the effects of early education on the social development of young children have been handicapped by a dearth of suitable criterion measures (Zigler & Trickett, 1978). The purpose of this project was, therefore, to develop a set of objective criteria for assessing the social competence of three-to five-year-olds in the preschool.Social competence is a hypothetical construct with no universally accepted meaning (O'Malley, 1977). It is a complex notion that involves cognitive as well as affective and conative variables which are difficult to separate (Anderson & Messick, 1974). For psychometric purposes it has been operationalized in multi-dimensional terms (Circus, 1975). Some have approached it from a personality trait or interpersonal relations point of view and have used teacher ratings of coping styles in social conflict situations to measure it (Kohn & Rosman, 1972). Only a few have attempted to assess the social competence of children by direct observation of their behaviour in natural settings (White & Watts, 1973; Licberman, 1977). These have, however, used widely different criteria for judging social ability. Typically, both positive and negative indicators have been employed and the scores obtained have been combined in complex and sometimes arbitrary ways. The goal of this project was to identify a set of