The solo self-employed, i.e. those entrepreneurs operating without employees, are a very diverse group of individuals: from artisans, shopkeepers, independent contractors, artists, entertainers, to highly-skilled professionals. They are represented in all sectors of the economy and public life. Due to the observed heterogeneity, it is difficult to conduct meaningful research as well as implement effective government policies; there is a need to standardise the classification and typology of solo-self-employment. We undertake a comparative analysis of recent attempts of segmentation of solo self-employed and demonstrate that existing initiatives are diverse and not entirely conclusive. In this conceptually and methodologically oriented paper, we highlight the measures and characteristics found in recent research undertakings that are used to differentiate between various segments of self-employed. Based on that, we put forward some recommendations for future research on the diversity of solo self-employed, highlighting the need to arrive at a unified framework for distinguishing between different types of own-account workers.