Climate change mitigation is a cross-cutting policy issue that requires coordination between policy departments and different levels of governance. However, the constitutional division of responsibilities (polity) and changing political constellations in government and society (politics) are constraining factors for achieving a horizontal climate policy integration and vertical coherence. This is especially the case in the federal system of Germany which is characterized by high degree of independence of departments and interdependence of the federal and subnational level. In recent years, integrated climate mitigation strategies were increasingly employed as a new governance mechanism to cope with the challenges of climate policy integration, coherence and longterm planning. This paper analyses and assesses the impact of three integrated climate mitigation strategies in Germany, namely the 2007 federal government’s “Integrated Energy and Climate Program” as well as regional strategies from Baden-Wuerttemberg and Hamburg. It shows that existing approaches especially at federal level so far lack important strategic elements that would ensure longterm impacts. Baden-Wuerttemberg’s recently initiated strategy process might serve as a role model for other entities because it combines clear objectives and targets with institutional innovations, legal codification and broad participation. The case studies demonstrate that effective strategies not only require ambitious and targets and measures, but also a continuous process and dedicated strategic capacities. However, the impacts of strategies on actual policy development are hard to attribute.