Carsharing is just a small niche product on the mobility market. The proven positive effects of carsharing can contribute to solving traffic problems only if the number of carsharing customers grows. A household survey was used to investigate the awareness and the market potential of mobility service carsharing in Germany. The results show that the majority of the respondents do not know what the term "carsharing" means. Even within the subgroup of people who could explain carsharing, local carsharing offers are not well known. To measure the attitudes toward the different modes of transport and acceptance of the general idea to share a car with other people, statement batteries were used. On the basis of factor analyses with linear and logistic regression models, the factors are determined that influence whether a person likes carsharing. Furthermore, the correlation between attitudes and behavioral aspects is revealed. In this context, people with multimodal mobility behavior are found to be more open-minded for shared-use vehicle systems. Finally, by taking subjective (attitudes) and objective (current mobility behavior) criteria into account, the potential of carsharing is estimated.