Gosta Esping-Andersen's (1990) The Three Worlds of Welfare Capitalism has become one of the most cited works in social policy (over 20,600 Google Scholar citations; 20 October 2014). This path-breaking work, with its identification of three distinct forms of welfare capitalism in high income countries, has become the basis for a whole academic industry described as the Welfare Modelling Business (Abrahamson 1999; Powell and Barrientos 2011). According to Headey et al. (1997: 332), it has become a canon in comparative social policy against which any subsequent work must situate itself. Abrahamson (1999) notes that, since the publication of the book, every welfare state scholar has referred to Esping-Andersen's tripolar scheme. Scruggs and Allen (2006: 55, 69) remark that it ‘is difficult to find an article comparing welfare states in advanced democratic countries (or a syllabus on social policy) that does not refer to this seminal work’, and ‘it is hard to overstate the significance of the impact of The Three Worlds of Welfare Capitalism (TWWC) on comparative studies of the welfare state’. Its seminal status is evidenced by the extent to which it continues to be cited in articles on comparative welfare states. It also remains required reading for most (graduate) students of comparative political economy and social policy (Scruggs and Allen, 2008). Kröger (2011) claims that, with few exceptions, comparative social policy research is shaped by welfare regime analysis. Arts and Gelissen conclude that TWWC is a defining influence upon the whole field of comparative welfare state research (2010: 569). Danforth (2014) writes that the ‘three worlds’ typology has become one of the principal heuristics for examining modern welfare states. In short, TWWC is a ‘modern classic’ (Arts and Gelissen, 2002).