This contribution discusses a theory of entrepreneurship, its empirical base, and its implications. First, it argues that a psychological approach is necessary to understand entrepreneurship. Second, it argues that any theory of entrepreneurship should use active actions as a starting point — entrepreneurship is the epitome of an active agent in the market (rather than a reactive agent). Third, it discusses an action regulation theory to better understand the psychology of entrepreneurship. Fourth, it provides examples how this theory can help to understand entrepreneurial success. Finally, I suggest intervention programs to help entrepreneurs to be successful at growing their organizations.