Commercially available Bt cotton varieties were evaluated for efficacy and yield potential at three locations in West Tennessee in 2000. PM 1218 BG/RR was the yield leader at two of three locations and did not differ from the leader at the third location. Bollworm and tobacco budworm populations were relatively light on the drought-stressed cotton. Bollgard II evaluations were conducted at two locations to determine efficacy and yield potential of the single and two gene systems. Although sprayed plots required two insecticide applications for suppression of bollworm and tobacco budworm, other target caterpillar species of the Bollgard II system were not present in adequate numbers to measure efficacy.