Educational leadership sustainability depends not only on the effectiveness of incumbent school principals but also on the capacity of educational institutions to prepare future leaders systematically. However, succession planning is frequently conceptualized as a replacement mechanism rather than an integrated process of leadership development and organizational continuity. This study aims to synthesize the literature on leadership pipelines and succession planning for heads of educational institutions, clarify their conceptual relationship, and identify priorities for future research. An integrative literature review was employed to examine relevant scholarly publications addressing leadership development, talent identification, competency development, succession processes, and leadership transitions. The literature was analyzed through thematic synthesis to identify recurring concepts, organizational mechanisms, conceptual distinctions, and unresolved research issues. The synthesis generated three interconnected themes. First, leadership pipeline development represents a continuous process of cultivating leadership capabilities through progressive responsibilities, mentoring, coaching, and experiential learning. Second, succession planning functions as a strategic organizational mechanism for anticipating leadership needs, evaluating candidate readiness, preserving institutional knowledge, and supporting leadership transitions. Third, integrating these processes provides a conceptual foundation for aligning individual leadership development with institutional succession requirements. The study advances an integrative perspective that distinguishes leadership pipeline maturity from succession readiness while emphasizing their potential complementarity. It also identifies future research priorities concerning leadership competency assessment, equitable access to developmental opportunities, organizational context, and the relationship between leadership preparation and transition outcomes. This study contributes to educational leadership scholarship by reframing succession as an ongoing organizational capability rather than an isolated appointment decision. Its conceptual propositions require further empirical validation through longitudinal, comparative, and mixed-methods research across diverse educational settings.