Obesity is a global problem that is predominantly caused by the increasing adoption of a low-cost, Westernised diet that is rich in fat and sugar and a more sedentary lifestyle. The costs of this epidemic are substantial increases in Type 2 diabetes, cardiovascular disease and some types of cancer that are certain to place a huge burden on individuals, healthcare providers and society. In this review, we provide an overview of the chequered history of pharmacotherapy for the treatment of obesity and an analysis of the regulatory and commercial challenges for developing new centrally-acting drugs in this metabolic indication. The efficacy and safety of the drug candidates that are currently at the pre-registration phase, i.e., lorcaserin, Qnexa and Contrave, are critically assessed. The main focus, however, is to provide a comprehensive review of the wide range of novel CNS compounds that are in the discovery phase or early clinical development. The profiles of various clinical candidates in animal models of obesity predict that several new CNS approaches in the clinic have the potential to deliver greater weight-loss than existing agents. This article is part of a Special Issue entitled ‘Central Control of Food Intake’.