Participating in communities of practice (CoPs) is an important way of learning. For newcomers in such communities, the learning process can be described as legitimate peripheral participation (LPP). Although a body of knowledge on LPP has been accumulated from qualitative case studies, mostly focusing on the use of practices, the concrete mechanisms that shape the LPP process have not yet been systematically analyzed. In this study, we examined participation support structures with a focus on activities that senior CoP members demonstrate to foster newcomers' participation. The use of 8 distinct participation support structures was identified in interviews with experienced members of faculty student councils. A hierarchical linear model based on data from 68 newcomers in 14 faculty student councils was computed. The model showed that in addition to exposure time and CoP size, 2 participation support structures (recruitment strategies and accessibility of community knowledge) were predictive of the newcomers' level of participation. We conclude that senior members' specific participation support structures can facilitate or hinder newcomers' participation in CoPs and that the original LPP approach needs to be enhanced by taking participation support structures into account.