Abstract
This study examines actor influence during the policy process and collaborative environmental governance within the context of environmental policy. Guided by interest group mobilization theory and the Advocacy Coalition Framework, the aim of this study was to analyze influence and power differentials among stakeholder groups, identify characteristics of policy learning, and determine how program indicators have led to positive environmental improvement. A longitudinal case study was conducted on California's Used Oil Program (UOP) looking at stakeholder representation through legislative bills passed from the 1980s to 2015, as well as indicator data from the UOP.