Core HIA documents, researchers and practitioners assert the significance of community participation in health impact assessment. Despite the rhetoric, there has been little critical examination of the role of community participation in HIA. Knowledge and debate regarding what constitutes community participation and how it may best be achieved is often confused and opinion is divided as to its usefulness and appropriateness for HIA. This paper does not seek to argue the merits or drawbacks of community participation; rather, the authors explore the origins and character of the current discord around public participation in HIA and provide a lexicon for moving practice and discussion forward. The authors argue that the origins of the participation problem stem from: (1) unexplored tensions within the Gothenburg consensus paper and other formative documents in the development of HIA; (2) inherent tensions arising from the dual origins of HIA, specifically Environmental Impact Assessment (EIA) and Healthy Public Policy (HPP); and (3) a lack of rigour and clarity relating to the terminology of community participation where community participation is used as a 'catch all' phrase for every situation without critical examination. In order to move debate forward, the authors advance a model, the Typology of Public Involvement in HIA, for guiding discussion of community participation. This model comprises a set of context-specific HIA approaches with varying degrees of public involvement. The model also presents a suite of defined terms for understanding and discussing participation.