This study examined the relations between students' social-emotional/behavioral functioning, engagement, and basic psychological needs satisfaction among a sample of N = 83 sixth grade students. A mediation model was tested to examine the role of needs satisfaction on the relations between engagement and social-emotional/behavioral functioning. Results indicated that engaged students have lower social-emotional and behavioral risk; however, this relation can be explained almost entirely by students' underlying satisfaction of basic psychological needs. These results suggest that targeting student engagement is not sufficient when attempting to improve social-emotional/behavioral outcomes; rather, students must also feel autonomous, competent, and experience a genuine connection with their school. Therefore, it appears that school-based programs designed to improve students' engagement in school might only have a limited impact on supporting social-emotional/behavioral functioning if basic psychological needs satisfaction is not also addressed.