This chapter provides an overview of the first two decades of the Global Trade Analysis Project (GTAP) - an effort to support a standardized data base and CGE modeling platform for international economic analysis. It characterizes GTAP in four different dimensions: institutional innovation, a network, a database and a standardized modeling platform. Guiding principles for the GTAP modeling framework include flexibility, ease of use, transparency, and symmetric treatment of production and utility fundamentals across regions. The chapter reviews core modeling assumptions relating to the regional household, private consumption behavior, welfare decomposition, the "global bank", treatment of the international trade and transport sector, and imports. Model validation and sensitivity analysis, as well as software issues receive attention as well. The chapter also offers brief overviews of the two major areas of application: international economic integration and global environmental issues. It closes with a discussion of future directions for the Project.