Purpose: This Engineer Regulation (ER) establishes policy for capacity development (CD) for international programs and projects conducted by the U.S. Army Corps of Engineers (USACE) and serves as the requirements basis document for CD planning and implementation for USACE international programs and projects. Engineer Pamphlet (EP) 5-1-1 (Capacity Development – International) has been developed as a companion document to this ER and contains additional details, instructions, and requirements for planning and implementation of CD on USACE international programs and projects.