The continuous increase in the prevalence of obesity has generated growing concern, having become an important challenge at a global level in economic and public health terms. In Portugal, the treatment of obesity presents significant problems in access to health services. In this context, there is a need to implement new management models that offer more effective responses. Centers of integrated responsibility, already implemented in this area, are a cutting-edge approach, and it is important to evaluate their performance and identify recommendations for improving the model. The main objective of this study is to assess the impact of implementing an obesity center of integrated responsibility on hospital performance. This study was conducted using a comprehensive multiple-case study approach, which was predominantly descriptive but also included explanatory elements. The methodological approach is a well-balanced mix of quantitative and qualitative analyses. The study evaluates various hospital performance indicators, encompassing the dimensions of access, production, efficiency, quality, and economic-financial, both before and after the implementation of the new model. The overall results indicate that the implementation of an obesity center of integrated responsibility led to improvements in hospital performance, particularly in the dimensions of access, production, and efficiency. While these findings are promising, the study also identifies areas for potential improvement in the model, such as organizational, functional, and legal aspects, including the method of granting incentives and the funding process. In the analyzed cases, this new organizational model proved to be a solution for improving hospital performance, particularly around obesity. These units can play a fundamental strategic role in the National Health System, contributing to access to specialized treatments, retention of professionals and financial sustainability.