This research included controls for both amount of extra-therapy attention focused on target behaviors and for quality and duration of attention provided during therapy. Two pairs of therapists each conducted one group for each of four experimental conditions: nonspecific therapy, nonspecific therapy + attention prompting, behavior therapy, behavior therapy + positive induction (procedures designed to maximize favorableness of expectancies). Sixty-five obese adults ( X̄ overweight = 52%) attended 12 weekly group sessions and 3-month and 2-yr follow-ups. Ratings of expectancies, credibility and therapist characteristics were equivalent in all experimental conditions. Attrition was low (9.7%) and Ss averaged 1–2 lb weight losses per week during treatment, while improving concurrently in eating habits, cardiovascular fitness and adjustment. However, only participants who were in groups conducted by the therapist pair which was rated especially ‘democratic’ maintained average weight losses at the 2-yr follow-up. These results demonstrate the potentially vital role of several ‘nonspecific’ factors in long-term outcomes associated with behavioral treatments for adult obesity.