This study was designed to assess the effectiveness of a multifocused (child-, teacher- and parent-focused) prevention program for Romanian preschoolers, targeting social-emotional competence development, as well as reduction of behavior problems. Fourteen classrooms were randomly assigned to the intervention and control conditions. Subsequent hierarchical linear analyses indicated that intervention-group children performed better on experimental tasks measuring emotion knowledge and social problem-solving strategies, and received higher assessments by their teachers and parents on measures of social-emotional competencies and externalizing problems. These results indicate that a prevention program combining intervention strategies for both high- and low-risk children is effective across a wide range of adaptive and maladaptive behaviors. Moreover, a short four-session parent group training employed to attract parent participation elicited an acceptable overall attendance rate (54%), indicating the sustainability of parent intervention in the context of community-based interventions. (author abstract)