The LCS is a longitudinal annual survey following a cohort of young adults born between 1988 and 1997 who grew up in Switzerland. The LCS was launched in 2013 and complements the Swiss Household Panel (SHP) by over-representing the second generation of immigrants (‘secondos’). The principal aim of the study is to observe the transition into adulthood with a focus on the life course and on vulnerability processes, comparing participants whose parents arrived in Switzerland as adults to participants whose parents have grown up in Switzerland. The cohort was split into five birth cohorts dependent on year of birth, namely 1988-90, 1991-92, 1993-94, 1995-96, and 1997-99.