29 men and 82 women (Ss' mean age was 46.82 yrs) who had achieved at least a 15-lb weight loss in a 20-wk cognitive-behavioral treatment program for obesity were asked 6-10 yrs after treatment about their current weights and January 1 weights for the past 5 yrs. Four types of weight change indices were developed. Comparisons of pre- and postprogram mean weight differences indicated that Ss had gained an average of 7.15 lb, but there had not been a mean increase in weight since a follow-up 5 yrs earlier. Importantly, 25.2% reported weights below their postprogram weights, and there were no mean differences between the sexes with respect to weight changes. A weight index based on percentages of weight gain since leaving treatment indicated that 41.5% had gained back more than 67% of weight that they had lost during treatment. Data from the different types of weight change indices indicated that substantially divergent conclusions could be drawn depending on the type of index used. (13 ref)