Among the theories that have been advanced for improving the participation of students in STEM is the postulation that family involvement in students' schooling is critical, as early as the precollege years. The prevalence of knowledge about the importance of familial support for students' success in STEM fields notwithstanding, the corpus of scholarship that explores the nexus between family support and Black student STEM success is limited. In this article, the authors utilize data collected through interviews, focus groups, and demographic questionnaires to explore the influence of immediate and extended family members in the STEM trajectories of eight undergraduates who were born in--or whose parents emigrated from--African or Caribbean countries. The qualitative study is grounded in Coleman's theory of social capital, which posits that there are 3 forms of social capital that families can bestow on children. These forms of social capital are: (a) obligations, expectations, and trustworthiness of structures; 2) information channels; and 3) norms and effective sanctions. Results from this investigation reveal that parents were intentional about the decisions that they made in their children's K--12 school years and that families sought out ways to support students through cocurricular engagement. Implications include a call to develop programs of support that recognize the important and often unique role that families and community play in the lives of Black (immigrant-origin) students, particularly those who are pursuing STEM degrees.