The category of the least developed countries (LDCs) was established in 1971 as a special group of developing countries characterized by a low income level and structural impediments to growth, and requiring special measures for dealing with those problems. The Committee for Development Policy (CDP) has been actively engaged in the establishment of the least developed country category and has since become highly recognized for its expertise in the identification of these countries. This revised edition of the Handbook on the Least Developed Country Category builds upon and updates information made available in a previous edition released in October 2015. It further underscores the Committee's dedication to making the methods and approaches used in the identification of least developed countries known to a wider audience of stakeholders and all those interested in finding solutions to the development challenges faced by these countries.