This paper contributes to improving understanding of how funders, practitioners and other stakeholders can support and facilitate transformation in adaptation to climate change. It uses the latest academic literature, as well as learning from practice, to put forward a conceptual framework for determining the likelihood of an adaptation initiative delivering transformation. The paper then applies the framework to examples of adaptation interventions being delivered as part of the Action on Climate Today (ACT) programme. ACT, a Department for International Development-funded initiative, supports 11 national and sub-national governments in South Asia to mainstream climate change adaptation into plans, policies and interventions. The paper presents a number of case studies from ACT that explore how the intervention is attempting to support transformation, and the signs that transformation is likely. These case studies use a theory of change approach to present evidence to assess how likely an intervention is to deliver transformation.