Three years of cooperative effort have resulted in information concerning the use and benefits or risks associated with the use of transgenic Bt cotton as compared with cotton varieties commonly grown in Mississippi that do not possess the Bt gene for endotoxin production. Comparison of an early season strategy for management of tarnished plant bug was also evaluated in the field-sized units at five locations in the state. Bt cotton appears to be a very competitive alternative to traditional insect management for the Mississippi cotton system. On average, yields were higher and insect-control costs were lower in Bt cotton than in fields of conventional cotton. Bt cotton was particularly important in preventing crop failure when tobacco budworm populations were high. Our data suggests that Bt cotton fields may be at greater risk to attack by other important pests, such as tarnished plant bugs and boll weevils, presumably due to the reduction of insecticidal inputs. However, attempts to prophylactically control plant bugs in this study did not have a significant benefit. Comparisons between certain sampling procedures are made, and our database may help determine the best or develop better sampling methods for pest and beneficial insect populations.