The stimulating private sector extension in Australian agriculture to increase returns from R&D project was a three year project to research, develop and test models to build the capacity of the commercial and private sector in delivering research and development and extension (RD&E) services to Australian producers. The project was in response to the trend towards increasing roles for industry and private services in delivering agricultural extension. This represents a shift away from traditional, government-funded extension services. Currently the extent of private sector involvement in extension varies across industries, depending on product markets, policy settings, regional issues and industry demographics. The private sector is now a well-used information source for farmers, however there is scope to enhance the capability of the private sector in delivering extension. Improving the capacity of private extension service providers will contribute to on-farm profitability and productivity gains.