The adolescent's process of brain maturation has important consequences for their ability to reason in decision-making processes. The notion of evolving capacity, for which age is not a sufficient indicator, implies a progressive vision of the nature and degree of participation according to the level of maturity. Health professionals are at the forefront of actively promoting young people's participation, supporting their decision-making about their own health, and seeing them as true partners and agents of change. The active participation of young people in all decisions that concern them is essential to make real progress in the field of adolescent health. This step implies a paradigm shift from "thinking for them" to "thinking with them".