The performance of Bollgard and non-Bollgard varieties based on lint yield/acre was examined in variety trials conducted from 1996-2001 in the Gulf Coast Region of Texas. A total of 196 comparisons between Bollgard or Bollgard Roundup Ready varieties and their recurrent parent (129 comparisons) or Roundup ready equivalent (67 comparisons) were made using the variety trial data. The data set was acquired from D&PL trials, state OVTs, county extension trials and consultant trials. All trials were grown using conventional management for insect and weed control. Comparisons were made across and within years for the entire Gulf Coast Region and for three distinct growing areas within this region. A dollar return per acre for the Bollgard varieties over and above the non-Bollgard varieties was figured using the base loan rate of $.5165. Bollgard varieties produced a 49-lb. yield increase over the non-Bollgard varieties when averaged across all years and location. Yield differences within years for the entire region varied from a low of 9-lbs./ac in 1998 to a high of 98-lbs./ac in 1999. The dollar returns per acre for the Bollgard varieties over and above the non-Bollgard varieties varied from a low of $4.65/ac in 1998 to a high of $50.62/ac in 1999 with an average dollar return per acre of $25.31.