As medical approaches to weight loss have been generally inadequate and unsuccessful, surgery has emerged as the primary treatment for morbid obesity. Early surgical procedures, the JIBs, involved bypass of variable lengths of small intestine to create malabsorption. Owing to an unacceptable incidence of complications with JIB procedures, including malnutrition, cirrhosis, liver failure, calcium oxalate renal calculi, and other problems associated with bacterial overgrowth in the bypassed bowel, restrictive operations were developed to limit intake rather than cause malabsorption. Evolution of gastric bypass and development of other modifications of purely restrictive procedures (eg, vertical banded gastroplasty and adjustable gastric banding) has continued to date. Despite accumulated knowledge from experience, no general agreement as to the optimal procedure has been reached, if one, indeed, does exist for any given morbidly obese patient. Analysis of results of surgical alternatives has always been hindered by a lack of comprehensive data collection, poor long-term patient follow-up, and lack of standardization of the technical aspects of the procedures and of reporting of results. With the increasing prevalence of morbid obesity and concomitant increase in procedures and number of surgeons performing them, these deficiencies will likely assume increasing importance.