The role of decentralisation processes and approaches in addressing climate change at the sub-national level and reducing territorial inequalities has become more critical. Decentralisation processes have been consistently questioned for their mixed experiences and results, especially in developing countries, where these reforms have failed to reduce territorial disparities. In turn, the role of each sub-national level in addressing climate change adaptation has been the subject of ongoing debate, as well as the consequences of decentralisation in weakening the capacity of states to implement systemic changes. Therefore, this paper was motivated by an interest in understanding how decentralisation processes in the context of developing countries could contribute to improving sub-national planning and response capacities to address disparities between cities and regions and the challenges of inclusive, equitable and coordinated climate change adaptation at all scales. The aim was to explore the frameworks and mechanisms through which decentralisation processes can address issues related to territorial disparities and climate change adaptation at the subnational level in the Latin American context. A first conclusion is that reframing the understanding of adaptive actions as the outcome of an essentially political process in terms of objectives, planning, implementation, and measurement of results implies, in turn, addressing decentralisation as a political instrument and not only as a goal in itself. Thus, decentralisation processes can be seen as an interconnector between sub-national climate governance and adaptation challenges and territorial disparities, rather than as a parallel process or a challenge in itself. A second conclusion concerns the flexibilization of policy mechanisms and instruments beyond the rigid institutional reforms in which the success of these processes is analysed, implemented, and evaluated, to incorporate the diversity of local, decentralised, and polycentric approaches, as well as flexible and soft planning mechanisms that incorporate various forms of scaling, participation, and accountability. In view of the above, this paper argues that the challenges of inclusive, equitable and coordinated climate change adaptation can contribute to deepening and rethinking decentralisation processes in Latin American countries -and in developing countries- in terms of strengthening capacities for planning and adaptive response at the sub-national level and reducing territorial disparity gaps. Finally, a conceptual framework is proposed as a starting point for future research to address the new challenges of decentralisation processes in relation to territorial disparities, climate change adaptation and the incorporation of flexible adaptive planning and governance mechanisms.