The self-employed are a heterogeneous group. Some are self-employed because they are good at it, while others are self-employed because they cannot find a better paying salaried job. Data from the CPS for prime age males show that workers are almost twice as likely to enter self-employment from unemployment as from paid employment. Furthermore, almost 22% of workers exit self-employment within the year with most returning to paid employment. This paper develops a framework for examining transitions between the labor market states of unemployment, paid employment, and self-employment. The self-employed fall into two groups: those who continue to seek paid employment in the wage and salary sector and those whose value from self-employment exceeds the expected value from continued search. The calibrated model is used to examine the effects of business startup costs on labor market transition rates. Doubling startup costs has very little impact on these rates.