Committed critical realist commentators on the economics discipline have not discussed, as far as I am aware, the regulation approach as an exemplar of critical realism (e.g., Baert 1996; Lawson 1989, 1995, 1997; Pratten 1997; Fleetwood 1999; Nielsen 2000). In some cases this neglect is due to a concern to develop a meta-theoretical critique of orthodox economics and/or to uncover critical realist aspects of heterodox economic theorising. In other cases it is due to a concern to show that Marx's own work at its best already illustrates critical realism (Bhaskar 1991: 143; Marsden 1998, 1999) or can be re-interpreted in critical realist terms (Pratten 1997; Ehrbar 1998, 2000; Kanth 1999). Where critical realists have shown interest in Marxism, their neglect of regulationism may reflect a judgement that regulationism can be safely ignored as just another current within a critical realist Marxism or, more likely, it occurs because the regulation approach, whether or not regarded as critical realist, simply does not appear within the horizon of those critical realists interested in economics. This chapter responds to this neglect in five ways: first, it introduces the regulation approach (hereafter RA) to readers interested in critical realism; second, it identifies four of its distinctive features as a specific current in heterodox economics; third, it reveals the critical realist assumptions that inform early regulationist work and suggests that it has engaged in middle-range retroductive inference to explain the specificities of Atlantic Fordism as an object of scientific investigation; fourth, it argues that this work has also developed some insights that are useful for critical realist purposes more generally notably in regard to the doubly tendential nature of tendencies and counter-tendencies, the co-constitution of objects and modes of regulation, the articulation of the economic and extra-economic, and issues of structure and agency; and, fifth, it offers some new retroductive arguments from a regulationist perspective about spatio-temporal fixes and contemporary capitalism. In addressing the first three themes, I focus on early contributions to the RA (especially by two Parisian regulationists, Aglietta and Lipietz) and also suggest how their initial arguments can be developed. This emphasis might seem odd given that the RA emerged over 25 years ago, that it comprises many different schools and currents, and that recent studies are much more complex and detailed. However, as regulationist concepts have become common academic currency and regulationists have become increasingly concerned with more middle-range issues in comparative institutionalism, the original methodological concerns of the pioneer regulationists tend to be forgotten. Yet it is these pioneer texts that most clearly state the key ontological, epistemological, and methodological assumptions underpinning the RA and neglect of which explains some of the weaknesses of current regulationism despite strengths in other respects. Scientific progress often depends on forgetting pioneering work but this does not always hold: classic texts may have a continuing relevance. This latter claim informs my discussion of the fifth set of issues.