The authors survey arguments that family firms should behave more like nonfamily firms and “professionalize.” Despite the apparent advantages of this transition, many family firms fail to do so or do so only partially. The authors reflect on why this might be so, and the range of possible modes of professionalization. They derive six ideal types: (a) minimally professional family firms; (b) wealth dispensing, private family firms; (c) entrepreneurially operated family firms; (d) entrepreneurial family business groups; (e) pseudoprofessional, public family firms; and (f) hybrid professional family firms. The authors conclude with suggestions for further research that is attentive to such variation.