In 1999, IRAC-US sponsored a bollworm monitoring program to determine if a widespread change in the susceptibility of the bollworm to the pyrethroid insecticides is occurring. Bollworm moths were collected and tested in Alabama, Arkansas, Florida, Georgia, Louisiana, Mississippi, Missouri, North Carolina, South Carolina, Tennessee and Texas. Over 7,400 moths were bioassayed from May through October 1999. Survival at the 5 g/vial dose of cypermethrin ranged from a low of 0% to a high of 34% in Missouri during June. Five states, Alabama, Louisiana, Missouri, North Carolina and South Carolina had greater than 10% survival during at least one month. Louisiana had greater than 10% survival at the 5 g/vial dose from May through August. Survival at the 10 g/vial dose of cypermethrin ranged from 0% to a high of 25% in South Carolina during June. Three collections: Louisiana (July), Missouri (June) and South Carolina (June) exceeded 15% survival at the 10 g/vial dose. The increasing tolerance of the bollworm to the pyrethroids demonstrated in this study, suggest that maintaining the effectiveness of the pyrethroids against the bollworm should become a higher priority in future resistance management plans.