In order to support the negotiation of international climate agreements and the achievement of global and national greenhouse gas emission reduction targets, regional and sub-national coalitions have emerged. This doctoral thesis analyses local climate mitigation strategies, based on voluntary climate agreements, and the political incentives promoting their adoption. Chapter 1 illustrates the strategies designed by a sample of 124 European large cities joining the EU Covenant of Mayors. It shows that cities’ contribution to climate mitigation can be notable, exceeding internationally agreed targets; however, this is limited to selected sectors, under their jurisdiction. Chapter 2 estimates electoral incentives for local governors to enter a climate agreement. On average, mayors committing to reduce greenhouse gas emissions in their municipality do not to lose electoral support at subsequent elections with stronger positive effects in cities with better economic conditions and a younger population. Chapter 3 unfolds a broader set of incentives encouraging local governors’ action. Private benefits (political income) from increased visibility and networking in a climate coalition seem to support the adoption of voluntary climate commitments. Overall, there is much scope to further engage local administrations in climate mitigation (and adaptation) action. Beyond this, future research could explore the contribution of city’s actions to “making finance flows consistent with a pathway towards low greenhouse gas emissions and climate-resilient development” (art. 2.1.c of the Paris Agreement).