Surgery currently appears to be the most effective method to curtail the effects of morbid obesity and all of its comorbid conditions. Although the ideal procedure has yet to be devised, Roux-en-Y gastric bypass has proved to be successful for many morbidly obese patients pursuing weight loss and increased health. As the technical aspects of this procedure become less cumbersome and the patient population increases, it is vital for radiologists to be proficient in the specific evaluation of these patients, in order to provide optimal care. Complications can be minimized, managed more efficiently, or prevented with prompt evaluation by the radiologist. It is important to appreciate the patency of both the gastrojejunostomy and the jejunojejunostomy, as well as adequate progression of contrast material before the patient is discharged (preferably 24-72 hours after surgery). Follow-up complications include anastomotic leak, staple-line disruption, stomal stenosis, occlusion of the Roux limb, small-bowel obstruction due to adhesions or internal hernia, and obstruction of the enteroenterostomy leading to acute gastric distention. These complications may be life threatening, since clinical symptoms are often inconclusive. To achieve optimal outcome, therefore, conventional radiographic and computed tomographic studies should not be delayed.