Social-emotional competence is a key developmental task during early childhood. This study examined concurrent relationships between maternal education and employment status, children's sex, ethnicity, age, receptive vocabulary, emotional knowledge, attention skills, inhibitory control and social-emotional competence in a sample of 146 preschool, low-income, ethnically diverse children from Head Start classrooms. Multilevel models demonstrated that inhibitory control played a significant role in the concurrent prediction of teacher ratings of social-emotional competence above and beyond other variables associated with social-emotional competence. Children who demonstrated better inhibitory control were more likely to be rated higher on social skills and lower in internalizing behaviors. Findings suggest that early identification of inhibitory control difficulties may be beneficial for targeting children at risk for maladaptive outcomes. The contribution of environmental experience to the development of inhibitory control skills suggests there are many opportunities to intervene during early childhood. © 2008 Elsevier Inc. All rights reserved.