Administrators and policymakers increasingly rely on collaborative policymaking groups to inform policy development. While this trend is observed in a wide array of policy domains, it is particularly common in the regulation of natural resource-based industries which requires the simultaneous consideration of an interrelated set of economic, technical, and social factors. In this article, we examine outcomes associated with collaborative policymaking groups involved in informing state aquaculture policy, referred to herein as aquaculture partnerships. We define outcomes here as consequences on relevant contextual conditions (social, political, and environmental) that follow from the work or design of collaborative processes. Using data collected through an online survey of partnership participants ( n = 123), we examine individual and procedural factors that significantly associate with partnerships’ positive or negative influence on a set of policy and social outcomes, as perceived by their participants. Overall, we find that participants’ ability to mobilize scientific and technical resources to achieve group objectives, perceptions of procedural fairness, and individual-level learning are all positively associated with partnership influence on policy and/or social outcomes. We conclude our article by highlighting the value of this research for both scholars and practitioners interested in better understanding collaborative group dynamics and outcomes relating thereto.