The heterogeneity and highly diverse nature of the SMEs population represent a core challenge for SME policy frameworks. This paper discusses if and how typologies can help policy makers to better understand the wide diversity of SMEs and entrepreneurs. It proposes a policy perspective for analysing typologies, and reviews 169 typologies to assess their relevance for policy making. The paper presents a number of actionable typologies, as examples of how policy relevant SME and entrepreneurship typologies could be developed. The paper was developed in the context of the OECD SME and Entrepreneurship Strategy.