In the treatment of morbid obesity, simple gastric restrictive methods such as silicone adjustable gastric banding, vertical banded gastroplasty, and nonadjustable gastric banding often fail to control weight in the long run or give rise to intolerable side effects. Here we review our results from conversion of such failures to Roux-en-Y gastric bypass. The study comprised 44 patients (median age 42 years, range 24 to 60 years) who underwent revision surgery in 1996 and 1997. Body mass index at revision was 35 kg/m(2) (range 21 to 49 kg/m(2)). Previous bariatric procedures included silicone adjustable gastric banding (n = 26), vertical banded gastroplasty (n = 13), and gastric banding (n = 5). The most common reasons for conversion after silicone adjustable gastric banding and nonadjustable gastric banding were band erosion (n = 12) and esophagitis (n = 11). Staple line disruption (n = 12) with subsequent weight loss failure was the primary cause after vertical banded gastroplasty. There were no postoperative deaths or anastomotic leaks. One patient underwent reexploration because of an infected hematoma. Reflux symptoms and vomiting resolved promptly. At global assessment 2 years later, 70% of the patients were very satisfied. Median body mass index had decreased to 28 kg/m(2) (range 18 to 42 kg/m(2)). No patient was lost to follow-up. As reported previously, failure after vertical gastric banding can be treated by conversion to Roux-en-Y gastric bypass with good results. In this study we found that failure after silicone adjustable gastric banding can be treated successfully with Roux-en-Y gastric bypass as well.