In this issue of Gastroenterology Clinics, guest editor Dr. Lee M. Kaplan brings his considerable expertise to the topic of Management of Obesity, Part I:  Overview and Basic Mechanisms. Most of the world's population live in countries where being overweight and obese is more life-threatening than being underweight. This preventable disease leaves patients with a cascade of health problems, resulting in serious stress and impact on global economies and healthcare systems. This issue, the first of two, addresses basic mechanisms and contributors of obesity, along with health care disparities and access.. Contains 16 practice-oriented topics including the many forms of obesity; genetic contributions to obesity; health complications of obesity; the effect of obesity on gastrointestinal disease; disparities in access and quality of obesity care; and more.  Provides in-depth clinical reviews of management of obesity, offering actionable insights for clinical practice.  Presents the latest information on this timely, focused topic under the leadership of experienced editors in the field. Authors synthesize and distill the latest research and practice guidelines to create clinically significant, topic-based reviews.