The prevalence of overweight and obesity in adolescents has quadrupled over the last 30 years, with signifi cant consequences for life expectancy. The main non-pharmacological intervention for these conditions is lifestyle modifi cation. This experience report describes an interdisciplinary intervention based on the Transtheoretical Model (TTM), delivered to a group of obese adolescents with the aim of increasing motivation for lifestyle modifi cation, evaluating motivation to change health-related behaviors, and discuss techniques to facilitate the evolution through the stages of change. The study involved thirteen participants with a mean age of 16.32 years (SD = 1.21), of whom fi ve were male and a eight, female. The purpose of this report is to describe how the processes for change can increase motivation for lifestyle change in this population. At the end of the intervention, participants showed increased motivation to exercise regularly and improve eating habits, as well as a mean overall weight loss.