Background: Globally, and in India, the research literature on vaccination highlights importance of community engagement in achieving national vaccination goals. However, community engagement, and “community” itself, are not well-defined and remains underutilized approach to realize health equity in this context. There is also paucity of literature on community engagement’s effectiveness in achieving vaccination outcomes. To address that gap, this study interviewed influential 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. Using Schutz’ Social Phenomenological theory, an a priori framework derived from the Social Ecological Model was used to guide coders’ 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: Interpretation of the data elucidated commonly-held understanding of terminology and engagement interventions by elite 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 optimally should function, the combined group articulated its importance 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.