This report provides a summary of the technical workshop on costs and benefits of adaptation options, organized under the Nairobi work programme on impacts, vulnerability and adaptation to climate change. The workshop was held in Madrid, Spain, from 22 to 24 June 2010. Discussions at the workshop addressed methodologies for assessing costs and benefits of adaptation options and how these methodologies are applied in and across different sectors. Participants also considered the role of assessments in the overall adaptation planning and implementation cycle, in particular how assessments assist
in identifying appropriate adaptation measures and practices and in avoiding maladaptation. The report includes a summary of recommendations and concludes with issues for followup and further consideration under the Nairobi work programme