The present paper reconstructs and analyses the assumptions – i.e. the policy theory – underlying the development of the SME and Entrepreneurship Policy Program in general and the Establishment Act and the Loan Guarantee (BBMKB) in particular between 1982-2003. The analysis links these assumptions to policy output results and policy effects. We find that the foundation of the policy theories of the Establishment Act and the Loan Guarantee requires improvement with respect to implicit assumptions and lacking warrants. We also find that the implied policy effects cohere with formal policy objectives.