It defines adaptation as the outcome of reduced exposure and vulnerability to climate risk and increasing resilience to the potential adverse impacts of climate extremes. The objective of a monitoring and evaluation framework for adaptation is therefore to assess if countries over time are able to reduce the exposure and vulnerability of people and infrastructure to natural climate variability and anthropogenic climate change. Cambridge University Press, Cambridge and New York. This chapter explores the main objectives and challenges for monitoring and evaluating adaptation at the national level. Some of the challenges discussed equally apply to adaptation projects and programmes. The chapter also briefly reviews some theoretical approaches to monitoring and evaluating adaptation and compares these with the approaches currently being designed and implemented by countries.