The mission of the Agricultural Model Intercomparison and Improvement Project (AgMIP) is to improve significantly agricultural models and scientific and technological capabilities for assessing impacts of climate change and other driving forces on agriculture, food security, and poverty at local to global scales. To enable this mission, AgMIP aims to create a next-generation knowledge platform for agricultural modeling worldwide, and to conduct coordinated regional and global assessments. A specific goal is to collaborate with regional experts in agronomy, animal sciences, economics, climate, and information technologies to build a strong basis for applied simulations addressing key food security questions, including adaptation to climate change. The AgMIP Charter lays out the structure and governance for achieving these goals and describes how national research programs can interact with AgMIP. AgMIP Partners are research programs in defined geographic areas, each having its own leaders and management structure and each being responsible for its activities, work products, and finances. National and Regional Partners are autonomous programs, operating at country or regional scales that contribute in specific ways to AgMIP initiatives. For example, AgMIP has developed new methods for protocol-based Regional Integrated Assessments that could be undertaken by participating countries. AgMIP activities in Brazil will be highlighted.