The private sector plays an important role in supporting green growth in developing countries. As a result, there is increasing emphasis for development co-operation providers to integrate private sector engagement (PSE) approaches into their programmes on green growth and climate change. This paper provides an overview of activities in this area, estimating that 22% of climate-related development finance supported PSE activities in 2013. It also presents a stock-taking of efforts to: mobilise private climate investment, promote green private sector development and harness skills and knowledge of private actors. The paper highlights some challenges and lessons learned, such as the need for PSE to target a wider range of environmental issues, the importance of investing in integrated approaches to enable the development of pipelines, and the need to align private sector approaches with national contexts. The findings in this paper contribute to the discussion on how development co-operation providers can improve the effectiveness of PSE approaches to promote green growth and climate action, and may be a useful starting point to guide evidence-based policy relevant research.