In the San Francisco Bay and Sacramento-San Joaquin Delta of California (Bay-Delta), sea level rise and flooding will harm communities and critical infrastructure, prompting planners and policymakers to focus on nature-based solutions such as wetlands. Wetlands can buffer storm surges, control erosion, and provide flood protection that is itself adaptable; wetland migration into upland areas as sea levels rise creates flexible flood protection. Wetlands also provide numerous co-benefits for habitat and communities. Human alteration for development and agriculture removed or altered over 95% of these wetlands. Regional policies and funding increasingly promote multi-benefit wetland restoration for social and ecological benefits. This project examines the social and policy landscape of wetlands restoration in counties of the Bay-Delta through a mixed methods social science approach. The two primary research tasks rely on different methods and data sources: 1) a quantitative analysis of wetland projects in the Bay-Delta from the EcoAtlas database will examine the extent of restoration projects and patterns of collaboration; 2) qualitative case studies of 10 projects will use interviews with project partners, funders, regulators, and regional stakeholders to understand benefits of and barriers to wetland restoration projects. Construction of a network of restoration projects and their partners from the EcoAtlas database enables social network analysis of partnerships among organizations on different restoration projects. A modeling approach examines how key factors of organizational capacity and project benefits affect investment decisions. The project case studies examine how long term projects evolve and adapt over time with changing science, priorities, and staff transitions. Additional interviews with practitioners, policymakers, and planners in the Bay-Delta supplement the case studies to understand key governance challenges and priority benefits. By examining the process of restoration projects, interviews can provide a deeper understanding of stakeholder experiences on projects of differing sizes, habitats, locations, and funding. The interviews will focus on how partners perceived or experienced collaboration, funding arrangements, regulatory processes, co-benefit priorities, and community engagement. Comparisons of findings from the project case studies will identify trends in benefit priorities across space and time, common barriers requiring regional solutions, and instances of cooperation or conflict unique to different projects. This work will generate actionable recommendations for wetland restoration implementation in the Bay-Delta, and contribute theoretical advances to growing environmental governance literature on collaborative governance and environmental management, especially for multi-benefit nature-based solutions and climate change adaptation.