Background: Globally, and in India, research has highlighted the importance of community engagement in achieving national vaccination goals and in promoting health equity. However, community engagement is not well-defined and remains an underutilized approach. There is also paucity of literature on community engagement’s effectiveness in achieving vaccination outcomes. To address that gap, this study interviewed Indian vaccination decisionmakers to derive a shared understanding of the evolving conceptualization of community engagement, and how it has been fostered during India’s Decade of Vaccines (2010-2020).Methods: Semi-structured interviews were conducted with 25 purposefully sampled national-level vaccine decisionmakers in India, including policymakers, immunization program heads, and vaccine technical committee leads. Participants were identified by their ‘elite’ status among decisionmakers in the Indian vaccination space. Schutz’ Social Phenomenological Theory guided development of an a priori framework derived from the Social Ecological Model. The framework helped organize participants’ conceptualizations of communities, community engagement, and related themes. Inter-rater reliability was computed for a subsample of coded interviews, and findings were validated in a one-day member check-in meeting with study participants and teams. Results: The interviews successfully elucidated participants’ understanding of key terminology (“community”) and approaches to community engagement propagated by the vaccine decisionmakers. Participants conceptualized ‘communities’ as vaccine-eligible children, their parents, frontline healthcare workers, and vaccination influencers. Engagement with those communities was understood to mean vaccine outreach, capacity-building of healthcare workers, and information dissemination. However, participants indicated that there were neither explicit policy guidelines defining community engagement nor pertinent evaluation metrics, despite awareness that community engagement is complex and under-researched. Examples of different approaches to community engagement ranged from vaccine imposition to empowered community vaccination decision-making. Finally, participants proposed an operational definition of community engagement and discussed concerns related to implementing it.Conclusions: Although decisionmakers had different perceptions about what constitutes a community, and how community engagement should optimally function, the combined group articulated its importance to ensure vaccination equity and reiterated the need for concerted political will to build trust with communities. At the same time, work remains to be done both in terms of research on community engagement as well as development of appropriate implementation and outcome metrics.