Because of the current and projected impacts on climate due to the high levels of greenhouse-gas (GHG) emissions, adaptation is a necessary strategy at all scales in a changing climate. At its 17th session, the Conference of Parties (COP) to the United Nations Framework Convention on Climate Change (UNFCCC) established the National Adaptation Plan (NAP) process as a way to facilitate effective adaptation planning in Least Developed Countries (LDCs) and other developing countries. The four key elements that need to be undertaken in the development of NAPs are: Laying the groundwork and addressing gaps; Preparatory elements; Implementation strategies; and Reporting, monitoring and review. Implementation strategies in the NAP process involve decisions related to climate risk management, which have to be based on reliable, relevant, usable and timely climate information. A number of activities in the different elements of the NAP process require effective and timely climate services consisting of the collection of climate data; generation and provision of a wide range of information on past, present and future climate; development of products that help improve the understanding of climate and its impacts on natural and human systems; and the application of these data, information and products for decision-making in all walks of life and at all levels of society. This publication identifies such activities and highlights the role of climate services for the different elements of the NAP process.