Retention, persistence, and completion are distinct, yet interconnected concepts used by policymakers, educational leaders, and researchers to assess college student progress and institutional accountability. We organize theoretical frameworks addressing the complex factors addressing these outcomes into three concentric layers: the Core (psychological and motivational drivers), the Orbit (integration, engagement, and institutional support), and the Galaxy (structural, cultural, and developmental contexts). Vertical transfer is conceptualized as a strategic pathway to a bachelor’s degree, contributing to retention, persistence, and completion in postsecondary education. Within the Core–Orbit–Galaxy structure, we examine theoretical frameworks for understanding vertical transfer students’ experiences and outcomes. While previous research on transfer, retention, persistence, and completion has informed policies and practices promoting college completion, the increased focus on initiatives such as the College Completion Agenda has led to unintended outcomes and complex tensions. We propose several data-driven, evidence-based, and advocacy-oriented strategies to address these challenges and advance the completion agenda.