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 policyrelevant research. Substantive contributions were made by Till Bajohr on the analysis of climate-related development finance flows supporting private sector engagement. The research was conducted under the auspices of the DAC Network on Environment and Development (ENVIRONET).