Product Development Partnerships (PDPs) are playing an increasingly important role in the development of new medicines for neglected diseases of the developing world; however, there has been limited information on their funding and expenditure patterns. This paper analyses funding for the 14 PDPs working on neglected disease research and development (R&D) by using unpublished data from the Global Funding of Innovation for Neglected Diseases (G-FINDER) project, which surveyed 2007 global investments into R&D of products for neglected diseases. PDPs captured US$469 million or 23% of 'external' R&D funding for neglected diseases, i.e. funding granted by donors to research organisations, as opposed to internal investments by donors. PDP's funding sources were highly concentrated with the Gates Foundation providing nearly half of PDPs' combined income (49%) and four public funders (the US Agency for International Development (USAID), the UK Department for International Development (DFID), the Dutch government and Irish Aid) providing 28%. PDPs collectively spent US$262 million on R&D activities in 2007, with 88% of this expenditure going to academic institutions, contract research organisations and companies in the developed world. Our analysis confirms the central role played by PDPs in R&D for neglected diseases, but highlights the need to diversify their funding sources.