Background: A first generation of adolescents with Down syndrome have grown up in Norway's inclusive society. This study explored their friendships and social leisure participation, mainly as it is reflected through their subjective experience. Method: The analysis is based on qualitative interviews and observations of 22 teens aged 17 years. Results: Generally, the adolescents described their social life as rich and varied, occurring in several contexts with different companions. Their thoughts of friendships were quite extensive, also including less close relationships. Three main contextual patterns of social participation were revealed: (a) the "family at home" pattern, (b) the "peer group" pattern and (c) the "arranged company" pattern. The relationship between the national policy on social inclusion and these findings is discussed. Conclusion: To understand the barriers and opportunities in the social life of Norwegian adolescents with Down syndrome, it is essential to acknowledge the extent of their experiences with friendship and the characteristics of their social participation patterns.