The aim of this study was to examine how adolescent students' sense of relatedness toward parents, teachers, and peers were differentially related to engagement, disaffection, achievement, and well-being. Two longitudinal studies were conducted among Filipino high school students. Study 1 focused on how sense of relatedness was associated with academic outcomes (engagement, disaffection, and achievement), while Study 2 focused on how relatedness was associated with well-being. Results of Study 1 showed that students' sense of relatedness predicted both initial levels and changes in engagement and disaffection, which in turn, mediated the effects of relatedness on subsequent academic achievement. Parental relatedness seemed more important for academic achievement compared to teacher and peer relatedness. In Study 2, sense of relatedness was found to be associated with positive and negative affect. Findings of this study provide evidence for the importance of relatedness in facilitating optimal outcomes and suggest that different types of relatedness may have differential effects. Theoretical and practical implications are discussed. (C) 2015 Elsevier Inc. All rights reserved.