Over the past three decades, the emergence of transnational partnerships between public and non-state actors in the areas of biodiversity and clean energy has represented an important dimension of the global trend towards the rise of this form of governance. The growing role of partnerships in biodiversity and clean energy governance can be explained by several concurrent factors. This chapter describes the methodology of the paper, summarizing the key characteristics of the three case studies and the rationale for using them in comparative analysis. It briefly presents the findings on the effectiveness of the three partnerships, trying to identify common patterns in terms of goal attainment, improved collaboration, creation of value for partners and wider sustainable development impacts. The chapter analyzes the findings against the conditions that are particularly relevant for explaining the variable effectiveness of partnerships.