The prevalence of obesity began rising about 1980, and one third of the US population is now obese. The medical risks of obesity are linked to insulin resistance, and diabetes prevalence follows that of obesity by a decade. This chapter approaches the treatment of obesity in the context of diabetes. The role of behavior modification, meal replacements and commercial weight loss programs are discussed. Medications that were approved before 1986 are approved for short-term use and are chemically related to amphetamine. Obesity medications approved after 1986 and are approved for long-term use, and include a lipase inhibitor and an inhibitor of norepinephrine and serotonin reuptake. All these drugs give modest weight losses of less than 5kg in excess of placebo. Rimonabant, a cannabanoid-1 receptor antagonist received an approvable letter from the FDA for the treatment of obesity, but its new drug application was ultimately rejected. Metformin and acarbose are 2 oral diabetes medications that give some degree of weight loss, as do the injectable diabetes medications, pramlintide and exenatide. Thiazoladinediones, sulfonylureas and insulin give weigh gain whereas the meglitinides and the DPP-4 inhibitors are weight neutral. Restrictive surgical procedures like the lap-band are one type of obesity surgery, and restrictive-malabsorptive procedures like gastric bypass is the other. Weight loss is more durable and the improvement in diabetes is more dramatic with the restrictive-malabsorptive procedures. Lifestyle change is the basis for all obesity treatments. Obesity medications and surgical procedures are useful adjuncts and all obesity treatments are best delivered by a team, as is the case with diabetes.