This thesis will explore the possible obstacles among Region Stockholm municipalities in promoting adolescents’ mental health and well-being through experimental governance. The thesis will examine the municipal and non-municipal points of view on specifically promoting adolescents’ mental health and well-being through experimental governance in the Swedish context with the use of urban sustainability transitions and transition management frameworks. The urban sustainability transitions will help us understand the role of cities in creating new modes of urban governing processes. In addition, the use of a transition management framework will help us to understand the importance of shifting from traditional management approaches by rather placing greater focus on innovative and design-oriented methods. This approach highlights the importance of learning by doing process rather than a reaching specific destination. In addition, I will use a qualitative research design that uses the methods of semi- structured interviews. The empirical findings are analysed with the help of thematic analysis through the theoretical frameworks and concepts. It has been demonstrated an observable slow- paced adoption of experimental governance, insufficient specific promotion of adolescents’ mental health and well-being, and distant relationship between experimental governance and promotion specifically adolescents’ mental health and well-being in the urban planning process.