Building on recent reviews on the costs and benefits of adaptation, this technical paper analyses the general methodological issues for estimating the costs and benefits of adaptation options, reviews new studies on the economics of adaptation in light of these methodological issues, and discusses the strengths and weaknesses of the studies and methods. Key findings from the paper include: the benefits of adopting multiple methods and approaches, including non-monetary ones, in accordance with the objectives of the assessment and the types of adaptation options to be assessed; the need for further methodology development, including in relation to the treatment of uncertainty, economic valuation and equity; and the continued lack of detailed analyses of the costs and benefits of adaptation, including in a form that is relevant to decisions on public funding. Parties may use the information contained in this technical paper as they consider implementing adaptation action under the Convention, including in the work under the Nairobi work programme, and particularly on its work area on socio-economic information. In addition, improved understanding and capacity for addressing the costs and benefits of adaptation is an important pillar in implementing enhanced action on adaptation at all levels