Communities of Innovation (COIs) is the approach yielding most value in the open innovation sector due to its strong developmental dynamics. While the literature has so far only analysed discrete facets of COIs, the general functioning of a COI is still largely unexplored. The purpose of this paper is to identify the interdependence between various functional elements of COIs and the effects of motives and cognitive success dimensions of a COI on planned activities based on the integrative-conceptual model of innovation. This study surveyed member groups of COIs and the structural equation modelling method for model estimates. The results showed the heterogeneous nature of motives among different groups derived from success dimensions and planned activities; solutions to the problem of critical mass for developers and facilitators; and expectations of solution quality and innovation diffusion. The findings implied that the successful establishment of group-related basic collectives is required to avoid premature abandonment of COIs. The integrative analysis of the present paper is the first-time approach of this kind providing evidence of a high level of interdependence between functional elements in different groups in COI.