Using a linked employer-employee data set for Germany, this paper analyzes labour fluctuation and wage setting in a cohort of newly founded and other establishments from 1997 to 2001. We show empirically that start-ups tend to have higher labour turnover rates, ceteris paribus. Moreover, bargaining coverage rates and wages in new firms are lower than in similar incumbent firms. Both the excess labour fluctuation and the wage differential are shown to decline and become insignificant over time as the newly founded firms mature. Our results imply that it takes a new firm only a few years to become an incumbent firm.