DFID Policy Division’s Investment, Competition and Enabling Environment (ICEE) team commissioned Bannock Consulting Ltd to examine how public-private sector dialogue (PPD) can support investment climate improvement. The consultants focused on DFID’s and the European Union’s field experiences with PPD processes and mechanisms in their private sector development programmes. The paper looks at dialogues spanning many continents, political and social systems, ranging from highly formal and structured to informal and ad hoc. It identifies success factors and lessons learned, and includes a helpful list of dos and don’ts for donors.