This study examined the hypothesized relationship between social adjustment, as measured by perceived social support, self-concept, and social skills, and performance on academic achievement tests. Participants included 27 teachers and 77 fourth- and eighth-grade students with diverse academic and behavior competencies. Teachers were asked to select one student for each of the three participant nomination categories: undeveloped academic competence, undeveloped behavior competence, and proficient academic and behavior competence. Multivariate analysis of variance results indicated that each participant group differed significantly on social skills, and students with proficient academic and behavior competence demonstrated significantly greater levels of self-concept than did those with an undeveloped behavior competence. None of the groups differed significantly on perceived social support. Structural equation modeling analyses revealed that the model predicting academic achievement from self-concept, social skills, and academic competence adequately fit the data. Indicators of social adjustment were discussed as intervention targets for programs intended to improve students' social competence and academic achievement. (Contains 2 tables and 2 figures.)