Climate change mitigation is a cross-cutting policy issue that requires coordination be-tween 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 integra-tion 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 interdepend-ence 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, co-herence and long-term planning. This paper analyses and assesses the impact of three in-tegrated 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 long-term 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, le-gal codification and broad participation. The case studies demonstrate that effective strategies not only require ambitious and targets and measures, but also a continuous pro-cess and dedicated strategic capacities. However, the impacts of strategies on actual poli-cy development are hard to attribute.