The pandemic of overweight and obesity continues to rise in an alarming rate in western countries and around the globe representing a major public health challenge in desperate need for new strategies tackling obesity. In the United States nearly two thirds of the population is overweight or obese. Worldwide the number of persons who are overweight or obese exceeded 1.6 billion. These rising figures have been clearly associated with increased morbidity and mortality. For example, in the Framingham study, the risk of death increases with each additional pound of weight gain even in the relatively younger population between 30 and 42 years of age. Overweight and obesity are also associated with increased co-morbid conditions such as diabetes, hypertension and cardiovascular disease as well as certain types of cancer. In this review we discuss the epidemic of obesity, highlighting the pathophysiologic mechanisms of weight gain. We also provide an overview of the assessment of overweight and obese individuals discussing possible secondary causes of obesity. In a detailed section we discuss the currently approved therapeutic interventions for obesity highlighting their mechanisms of action and evidence of their efficacy and safety as provided in clinical trials. Finally, we discuss novel therapeutic interventions that are in various stages of development with a special section on the weight loss effects of anti-diabetic medications. These agents are particularly attractive options for our growing population of obese diabetic individuals.