One constitutional part of project management is the management of teams, their actions, and their social mechanisms. Team processes, behavior, and agile practices used by team members play important parts in the success of projects. To reap benefits from these highly interactive and social-focused practices, team members need to feel safe to speak freely. We propose a model that conceptualizes the effects of psychological safety and (social) agile practices on team performance. The proposed model combines recent research from organizational psychology and agile information systems development to provide a better understanding of the team-level effects. Our findings from three case studies conducted in two large insurance companies and one software development company suggest that social agile practices positively influence psychological safety, transparency, communication, and ultimately productivity.