As many of the world’s poor and food-insecure people live in mountain regions, sustainable mountain development is an important part of the work of the Food and Agriculture Organization (FAO) of the United Nations (UN). Over the years, FAO has played the leading role in sustainable mountain development within the UN system; it was appointed task manager for chapter 13 of agenda 21 in 1992 and acted as the lead agency for the International Year of Mountains in 2002. From 2003 onward, FAO was also mandated by the UN General Assembly to lead the annual observance of International Mountain Day on 11 December. Every 2 years, FAO prepares the secretary general’s report to the UN General Assembly, which describes the status and progress of sustainable mountain development at the national and international levels and provides suggestions for consideration by the Assembly. FAO is a member of the Mountain Partnership and hosts its secretariat.This review of the latest actions of FAO’s program on sustainable mountain development, watershed management, and forest hydrology—which includes normative work, field activities, and support to international processes—updates our previous statement (Manuelli et al, 2014) and summarizes the latest achievements of the Mountain Partnership.</emph>