Obesity is the result of a complex interplay among several factors leading to medical, functional and psychosocial consequences that markedly reduce life expectancy and impair quality of life. Is obesity itself a disease? Is obesity a brain disease? Who should treat obesity? This paper is a narrative review aimed to describe and to argue the prevalent position of some major Italian scientific and academic institutions dealing with obesity. According to the recent statements and recommendations published by the Italian Society for Obesity (SIO) and the Italian Society for the Study of Eating Disorders (SISDCA), the management of obese patients should include five main levels of care: (1) primary care, (2) outpatient treatment, (3) intensive outpatient treatment, (4) residential rehabilitative treatment, and (5) hospitalization. Ideally, patients suffering from obesity need a multidimensional evaluation intended to design an individualized treatment plan applying different procedures and therapeutic strategies (diet, physical activity and functional rehabilitation, educational therapy, cognitive-behavior therapy, drug therapy, and bariatric surgery). This thorough approach should address not only weight loss but also quality of weight loss, medical and psychiatric comorbidity, psychosocial problems, and physical disability. Such management of obesity requires an effective multiprofessional team, while health services have to overcome a number of administrative and organizational barriers that do not account for diseases requiring resources and professionals from different areas of medicine. Integrating several competences in a team-based approach demands specific education, skills and expertise. As for other diseases, the principles of complexity theory may offer a model useful to implement both teamwork and care delivery for patients with obesity.