This essay engages with Wimmer's Ethnic Boundary Making to consider how cultural processes feed into inequality. It describes the strengths of the book, relates it to my early work, and draws on Lamont, Beljean, and Clair (forthcoming), to describe two types of identification processes (racialization and stigmatization) and two types of rationalization processes (standardization and evaluation) that contribute to an understanding of the relationship between symbolic and social boundaries. It stresses similarities and differences between approaches and suggests possible points for convergence.Ethnic Boundary Making: Institutions, Power, Networks (Wimmer 2013) has the makings of a classic. The author takes on a vast and important topic, provides a bold and ambitious theoretical agenda, and engages in theory development by convincingly confronting his hypotheses with data of various kinds. As he goes along, he explains the implications of his findings for a wide range of theories and debates in sociology and beyond, and thus demonstrates the significance of these findings. The result is impressive because of Wimmer's mastery of American and European literature from various fields, his encyclopedic knowledge of ethnic group composition and differentiation from around the globe, and his ability to use new statistical techniques to establish empirical patterns of group cohesion, differentiation and boundary work.One of the many theoretical contributions of the book is its presentation (in chapter three) of a broad typology of boundary changes, which appears to apply to all configurations possible. This is followed by another more elaborate typological analysis in chapter four that discusses the conditions that help us predict boundary work (with a focus on the institutions, power and networks singled out in the title of the book). The theoretical generativity of the analysis, and its wide applicability to fundamental sociological questions, are simply remarkable.Wimmer's focus on the making of groupness (and more specifically, ethno-national groupness) shares much with my own work on boundaries and classification, from its insistence on not predefining the categories through which individuals self-identify. Indeed, this is precisely the inductive approach that I used in Money, Morals and Manners (Lamont 1992) and The Dignity of Working Men (Lamont 2000), where I asked professionals, managers and workers to produce boundary work in the context of interviews -that is, to describe who they feel similar and different from, inferior and superior, and so on -so as to tap where they draw lines and what criteria they use to draw such lines. The conclusion of Money, Morals and Manners opened up the question