Wikipedia
GTAP (Global Trade Analysis Project) is a global network of researchers (mostly from universities, international organizations, or the economic ministries of governments) who conduct quantitative analysis of international economic policy issues, especially trade policy. They cooperate to produce a consistent global economic database, covering many sectors and all parts of the world. The database describes bilateral trade patterns, production, consumption and intermediate use of commodities and services. There are satellite databases for such things as greenhouse gas emissions, and land use. There is software for aggregation to different levels of sectoral and regional detail.
The GTAP project is coordinated by a team at the Center for Global Trade Analysis (CGTA), based in the Agricultural Economics Department at Purdue University. The team maintains a global computable general equilibrium model, which uses the GTAP database. Besides the core model, there are many variants (including one focused on agricultural analysis), each focusing on a different issue in economic policy analysis.