Purpose: This study aims to investigate the adolescents’ perspectives about 1) the changing process promoted by a weight management program; 2) the factors which may act as facilitators and barriers to obesity management; 3) the strategies that should be included in order to design a successful weight management program. Methods: Data were collected by in-depth interviews and focus group discussions with 16 overweight adolescents, aged 12 - 18 years. Thematic analysis was used for analysing the data. Results: Findings suggest that attributions (internal and external), functions (barriers and facilitators) and perceptual changes (lifestyle and body and mind changes) play distinct roles in the changing process. Interactions recognized as high quality ones, acquisition of new knowledge and competencies and encouragement throughout the process, were identified as facilitators. Negative patterns of interaction, collection of anthropometric data and internal resistances, were identified as barriers. The relevance of developing systemic interventions including family and peers, and the use of Information and Communication Technologies were highlighted. Conclusion: This study aims to contribute for a deeper understanding of the factors and processes behind adherence to weight management. Implications for the design of future more effective strategies and implementation of appropriate interventions are discussed.