The primary commercial features of recently released transgenic cotton (Gossypium) cultivars are their respective pest management traits, including, tolerance of the herbicides Buctril(R) (bromoxynil) and Roundup Ultra(R) (glyphosate), and the capacity to synthesize a Bacillus thuringiensis (Bt) endotoxin for control of lepidopteran pests. Many transgenic cultivars have been offered for sale with fewer years of public testing than most growers and their advisors would have liked. Lack of time and resources may have resulted in some having been sold in locations with no previous public testing in the immediate growing area. Despite the lack of public test information, the collective market share of transgenic cultivars has increased every year since their introduction, presumably because of high grower interest in their value-added, pest management features. Obviously, transgenic pest management traits strongly influence the pest management programmes that are appropriate for the transgenic cultivars, and the efficacy of the pest management programmes may positively affect yields and the costs of production. However, in Official Cultivar Trials (OCTs), comparison of the transgenic cultivars with non-transgenic cultivars has been done using only conventional and, frequently, a high level of pest management. Concerns, about the lack of public test data on transgenic cultivars, and about relying solely on OCTs for their evaluation, prompted Cotton Incorporated to convene a working group, the objective of which was to seek consensus among public and private sector researchers on how to enable growers to confidently choose the best cultivar and pest management technology for their situation. The drafting subcommittee of the working group proposed guidelines for cultivar evaluation to a joint meeting of SRIEG-61 (Southern Regional Information Exchange Group 61 - Cotton Breeding), and a new Regional Project in preparation, SRDC-9801 (Southern Regional Development Committee 9801 - Development of Genetic Resources for Cotton). Principal points of the proposal were that a minimum of 2 years of public test data should be available to growers at the time of first sale, and that the data should include comparison of transgenic cultivars with cultivars generally recognized as having high yield potential. The proposal also suggested that the testing should provide comprehensive economic evaluation of new cultivars by concurrently evaluating yields, fibre quality, and the efficacy and costs of the respective pest management programmes.