A computer program, named COTVAR, is being developed that will help with comparing performance of cotton varieties in state variety tests. At present, the program utilizes data from state variety tests in Arkansas, Louisiana, Mississippi, Missouri, and Tennessee. Each year, cotton varieties are evaluated at approximately 30 sites over these five states. Test performances from each state are made available in annual variety test publications and on the internet. COTVAR will enable easy comparison of varieties over the states by integrating data from multiple states into one file. Users can select specific test sites or regions and compare varieties, which are characterized by type (convention, single or stacked transgenes) and by status (commercially available, experimental, or obsolete). Data generated include yield, lint fraction, fiber properties, and specific morphological and host plant resistance traits.