Metabolic surgery is “the operative manipulation of a normal organ or organ system to achieve a biological result for potential health gain” 1. More recently, it has been applied to describe the stunning reversal of metabolic disorders noted after bariatric (weight loss) surgery. Indeed, the improvement in conditions such as type 2 diabetes mellitus, hypertension, dyslipidaemia and non-alcoholic fatty liver disease have been so dramatic that national obesity surgery societies have quickly added “metabolic” to their names to capitalise on the health benefits of these procedures. These recent findings, well-documented over the past 2 decades, have added a new dimension to bariatric surgery which hitherto was focused on weight loss, giving rise to the present specialty of metabolic-bariatric surgery (MBS). This paper looks at the various types of metabolic surgical interventions and analyses the purported benefits in improving each of these obesity-related metabolic disorders. The appropriate indications for surgery and possible complications arising are also discussed