Establishing and maintaining positive relationships with parents, non-familial adults, and peers are important tasks linked to social and academic adjustment during childhood and adolescence. Few studies have examined patterns of relatedness in youths' experiences with various social partners using person-oriented and variable-oriented approaches. The present research aims to address these limitations and provide new information about the antecedents and consequences of youths' experiences with parents, peers, teachers and mentors. In the first study, links between youths' perceptions of friendship intimacy and mothers' and fathers' reports of parental acceptance were examined among 246 Mexican American 7th graders. Three patterns of parent-peer linkage were identified using Latent Profile Analysis (LPA): Low Parent; Positive; and Low Friend. A mixed model ANCOVA indicated that youth in the Positive profile had higher bi-cultural orientations relative to other youth, reflected by their higher Anglo orientations, and familism and respeto values. Further, there was greater congruence between the familism values of youth and parents in the Positive profile than for youth and parents in the other profiles. Finally, univariate ANCOVA models indicated that youth in the Positive profile had better adjustment relative to youth in the Low Parent profile, but comparable adjustment to youth in the Low Friend profile. Findings revealed the benefit of a person-oriented approach to illuminate the within-group variability in parent and peer experiences and the unique cultural experiences of minority youth, as well as the implications of parent-peer linkages for the adjustment of minority youth. In the second study, links between youths' closeness with teachers, their social preference among peers, and their perceptions of peer competence were examined among 383 white, lower- to middle-class, rural students in the fall of 6th grade. Three patterns of teacher-peer relatedness were identified using LPA: Low Relatedness; Peer-Oriented; and Teacher-Oriented. A multinomial logistic regression analysis revealed that prosocial behavior in 5th grade positively predicted membership in the Teacher-Oriented and Peer-Oriented profiles in contrast to membership in the Low Relatedness profile, and aggressive behavior negatively predicted membership in the Teacher-Oriented profile in contrast to the Low Relatedness profile. In hierarchical linear regression models, indicators of relatedness with teachers and with peers and patterns of teacher-peer relatedness were uniquely associated with youths' social and academic adjustment across middle school. Findings also indicated a maladaptive synergistic effect for Low Relatedness youth, such that having a pattern of poor relationships in the school context was worse than the additive effects of the independent indicators of relatedness. The third study examined patterns of association among mentoring match characteristics in 565 youth and 554 mentors participating in the Big Brothers Big Sisters school-based mentoring program. Four distinct mentoring match profiles were identified using LPA: Intuitive; Disengaged; Sufficiently Trained; and Efficacious. Hierarchical linear regression models indicated that the Disengaged profile tended to have less positive mentoring relationship outcomes compared to other profiles. Youth age moderated associations between mentoring profiles and adjustment, such that profiles characterized by mentors' perceptions of sufficient pre-match training in combination with average to high mentor efficacy and engagement in social and academic activities was associated with more positive outcomes for older youth. Collectively, findings from the present studies support the use of person-oriented techniques to examine how features of relationships with parents, peers, teachers and mentors are connected in different ways for different youth and associated with a host of adjustment outcomes. Implications include the importance of assessing relatedness patterns to address youths' adjustment in family, school and mentoring program contexts.