The group of self-employed persons in the Netherlands is diverse and growing. In this paper, we report on a large survey, including incentivized experiments, among the Dutch working population (N=4,282) to analyze important pension-relevant preferences, traits, skills, and attitudes of the self-employed compared to employees. Our data contain a rich set of measures, including economic preferences, social preferences, personality traits, cognitive skills, financial skills, financial well-being, and attitudes toward pension saving. Data from the survey are enriched with demographic and socio-economic variables from register data provided by Statistics Netherlands. The exploratory analysis investigates differences between employees and the self-employed, where we distinguish between self-employed persons without personnel (solo self-employed), self-employed persons with personnel, and owner-managers. The results show that compared to employees, the self-employed in the Netherlands indicate having a higher willingness to take risks, are more patient, and are more optimistic (stated preferences). Interestingly, when using measures based on behavior (revealed preferences), differences between the self-employed and employees are smaller or even vanish. Regarding pensions, the self-employed consider themselves more knowledgeable, save extra or intend to do so in the future, feel more responsible for their own pension, but some groups of the self-employed tend to regard solidarity as less important than employees. There is considerable heterogeneity within the group of self-employed. Compared to other self-employed persons, the solo self-employed characterize themselves as having less financial security and a tendency of lower trust in institutions. The self-employed with personnel exhibit higher negative reciprocity and lower trust in public institutions than other groups of self-employed. Owner-managers tend to show higher negative reciprocity, higher financial literacy, and lower financial anxiety than other groups of ...