"This paper is part of the Compendium of Evidence on the Effectiveness of Innovation Policy Intervention. This paper examines publicly supported policies for entrepreneurship development. Entrepreneurship policies are directed to encouraging socially and economically productive activities by individuals acting independently in business. Their principal objective is to increase a level of entrepreneurial activity which is considered to be below the social optimum. Policies may be implemented directly to address entrepreneurs' needs e.g. business advice programmes or through broadcast methods such as education policy. We have attempted to locate and focus on evaluations that reported on additionality / net effect or that use methods of causal inference to determine the effectiveness and impacts of policy. While policies and programmes for entrepreneurship can be simplistically modelled as a series of inputs beginning with cultural change followed by general and then more specific skill development, it is hard nevertheless to assess impact or trace causality because of the difficulty of defining discrete units of input, the presence of confounding factors and the length of time over which effects can build."