1The notion of social mix has been widely accepted since the 1980s [1] as a legitimate means of distributing populations in space. This collective work edited by Éric Charmes and Marie-Hélène Bacqué sets out to probe the effects of using the notion in public policy and working to achieve social mix. The five contributions are highly diverse but their coherence is clearly conveyed by the introduction, the conclusion and the brief presentations by the editors that precede the chapters.

2In the first chapter, Marie-Hélène Bacqué asks how social mix as a public policy notion and aim affects common representations of classe populaire [working-class or relatively poor] neighbourhoods, critiquing the disqualification-naturalization of communities it entails. She begins by recalling Weber’s definition of the community – “a group defined by a feeling of membership, belief in a common heritage, by a tradition or shared origin” (pp. 19-20) – then shows that communities develop on different bases (geographical, religious, work-related, etc.), and that a person may therefore belong to several of them. From this perspective, communities are not merely social groups that individuals can withdraw into; they also provide resources, generate critical consciousness and transmit a power to act. Naturalizing communities makes it impossible to conceive and understand social change, she explains, particularly the processes by which the classe populaire has become desegregated, processes linked to longer education and a wider range of cohabitation, interaction and co-presence situations of the sort described in detail by Olivier Schwartz [2]. For Bacqué, the notion of social mix misrepresents the real issues operative in working-class neighbourhoods, issues related not to withdrawal into a community but on the contrary the transformation of such neighbourhoods due to the increasing diversity and increasingly precarious situation of this social group.

3In the second chapter the eminent American sociologist Robert Sampson offers a dense, detailed account of the theoretical framework of his Great American City. Sampson specializes in “the neighbourhood effect”; that is, the impact of neighbourhood characteristics on inhabitants’ social trajectories and outcomes. He shows that “ecological concentration of the truly disadvantaged” (whose lives are characterized by poverty, unemployment, family breakups, racial segregation and other ills) does affect levels of violent crime and mutual assistance but that this effect is not mechanical. Sampson develops two concepts that complexify analysis of segregation. First, the notion of a “mirroring” neighbourhood whereby he can claim that shared perceptions of disorder predict how a neighbourhood will develop and change – notably by following what Jean-Claude Chamboredon (1985) [3] described as the dynamics of “social construction of populations” – and that individuals settle in neighbourhoods with inhabitants whose perceptions they share. The second concept is “collective efficacy”, namely effective social regulation: a means of keeping crime low and a possible resource, including in segregated neighbourhoods. Sampson thus highlights the fact that these kinds of neighbourhoods may be resources; his analysis of the neighbourhood effect goes beyond a critique of segregation.

4In Chapter 3 the geographer Mathieu Giroud probes the ambivalent social effects of social mix in connection with the gentrification of classe populaire neighbourhoods. Promoting social mix in these neighbourhoods side-skirts the adverse effects that gentrification has on the most vulnerable components of the population. Classe populaire neighbourhoods get “rehabilitated” for the stated purpose of opening them up to the middle classes, but this relegates symbols of that group’s heritage to the category of aesthetics and has the effect of effacing the related, possibly conflictual social history of the place. Drawing on his study of a historically working-class neighbourhood of Grenoble, Giroud shows how social mix there is still marked by relations of domination and social control of the less advantaged group, though that group occasionally manages to put up “some resistance”.

5In Chapter 4, Stéphane Tonnelat draws on a review of the American literature and his own interactionist research on relations between passers-by to probe the effects of social mix in public space. He begins with a strict definition of public space – a place of anonymous co-presence – that distinguishes it from both private and neighbourhood spaces, the latter made up of secondary relations with more or less distant acquaintances. Then, instead of merely postulating an idealized role for public space as a place that instils a sense of solidarity in citizens, he takes a closer look at how socialization actually works in and by way of these spaces. His analyses show that in socially mixed public places, people acquire behaviours that promote generalized accessibility founded on a sense of equality; for example, there is no discrimination against minorities. In other words, situations of co-presence among individuals of diverse social and ethnic or migration origins work to instil values of tolerance and respect for difference.

6The last chapter is based on a collective study by Éric Charmes, Lydie Launey and Stéphanie Vermeersch. It is presented as a response to Jacques Lévy’s “urbanity gradient” theory, according to which spaces are hierarchically ordered by their functional and social diversity (or, in Tonnelat’s terms, their propensity to produce situations of anonymous co-presence). In that hierarchy, major metropolises stand opposed to peri-urban residential areas, the latter understood to foster attitudes of withdrawal into domestic space, private relations with similar persons and an overall exclusion of difference. On the basis of qualitative interviews with residents of the ninth arrondissement of Paris and residents of a well-to-do neighbourhood in a peri-urban town in the département of Yvelines, the authors conclude that “peri-urban areas are not a degraded version of cities”. They first show the diversity of peri-urban spaces, ranging from strongly classe populaire (areas likely to have noise pollution – airports, trains) to solidly middle-and upper-class districts. They then contend that while the peri-urban area they have studied is more socially homogeneous than most city centre neighbourhoods, the selective sociability of ninth-arrondissement residents tends to produce the same level of homogeneity. At the end of the chapter, Charmes and his colleagues note that no one is spared fear of the other. The discourse of ninth-arrondissement Paris residents proved more contemptuous and racist that that of peri-urban residents. The social mix characteristic of the city centre can therefore induce behaviour that is more segregational than in peri-urban areas.

7Across the five chapters, then, the notion of social mix is handled in two ways. First, the book suggests different ways of thinking about the notion as a public policy lever. The social mix “credo” has been used to justify the disqualification (and renovation) of working-class neighbourhoods of the sort studied by Bacqué; also to promote gentrification of central working-class neighbourhoods and to reduce segregation in such neighbourhoods, including ones once characterized by strong “collective efficacy”. The book thus leads us to greater caution or circumspection about the effects of the social mix idea. But the various contributions also probe the effects of real social mix. Tonnelat, for example, shows that social mix in public places can foster the emergence of skills favourable to tolerance and respect for others, whereas Giroud highlights how the co-presence of socially different groups can engender domination and social control. The strength of the book lies in just this cautious and ambiguous conclusion and its demonstration that the question of the effects of social mix is far from closed and deserves our continued attention. For while it is obvious that a more balanced spatial distribution of people and groups is not enough to resolve social inequalities, it would be unfortunate to neglect how it contributes to social reconfigurations.