In 2009, the first free-floating carsharing service in Germany was introduced: car2go in the City of Ulm. Since then, the number of these services has been largely increasing. Today, many providers are competing in the German carsharing market. This paper presents the evaluation of the car2go service in the Free and Hanseatic City of Hamburg. A systematic two-stage evaluation system was set up directly with the launch of the service in 2011, including two online surveys in 2011 and 2016. This paper first describes the survey approach including methodological issues and survey content, then analyzes the car2go users: their characteristics, their access to mobility tools, motivations, preferences, and daily travel behavior. Three user groups are distinguished: (1) Early Adopters 2011, (2) All Customers 2016, and (3) Active Users 2016. Third, findings for car2go users are compared with the general population based on data from the National Household Travel Survey (NHTS) “Mobility in Germany 2008” with a comparatively large sample size for the metropolitan area of Hamburg. The insights gained in these analyses give an up-to-date overview of users’ characteristics, their usage of the car2go services, and their general travel behavior in comparison to the general population.