Concrete City: Material Flows and Urbanization in West Africa. ArmelleChoplin. Wiley, New York, 2023, pp. xix + 240. <scp>ISBN</scp> 978‐1‐119‐81200‐5 (pbk).

There is currently a ‘material turn’ in the social sciences and humanities. A growing body of literature has shed light on the socio-political and historical life of certain globalized commodities, such as coal (Seow, 2022), oil (Shafiee, 2023) and copper (Rubbers, 2019). However, compared with these high-value things, building materials, especially ‘concrete’ that constitutes the backbone of contemporary urban production worldwide and our current crisis of Anthropogenic climate change, have received less scholarly attention (Simonetti & Ingold, 2018). If any, current narratives mostly focus on either the (re-)invention history of it in Euro-American contexts (Smith, 2024), or its external connection to geo-politics and economic profits dominated by Cold-War superpowers (Sneddon, 2015), while largely downplaying how the materiality of this socio-technical object and corresponding processes of production, distribution and consumption, as Armelle Choplin shows in her new book Concrete City, are inextricably linked with global capitalism, urban development and individual affect in the postcolonial world, let alone the least urbanized Africa. However, as a product of ‘money, materiality and verticality of concrete towers’ and ‘laboratory of planet-scale changes’ (p. 24), the rising African continent with rapid urban growth has rendered itself the ‘last frontier of capitalism’ (p. 7). Concrete, which is simultaneously a privilege for former colonizers, a symbol of national identity for postcolonial states, a regime of capital accumulation for businessmen, and a technology of mass construction for unskilled individuals, is adopted by Choplin as an entry-point to scrutinize capitalist urban production in West Africa and its local impacts. Here, Concrete City, a new icon of ‘Africapitalism’ (p. 15), is not confined to metropolises, but varying local realities of little-known cities along the Lagos-Abidjan Corridor, the longest chain of cities throughout West Africa whose postwar reconstruction was dominated and underpinned by concrete. Inspired by Jennifer Robinson's (2022) ‘comparative urbanism’ that rethinks decolonizing cities through elsewhere, her methodology integrates ‘material turn’ with ‘following the thing’ to track the ‘biography of concrete’ (p. 21) along its global value chain to analyse urban production and governance, in which various actors ranging from politicians, subcontractors, entrepreneurs, professionals to urban residents building their homes were all involved, based on multi-sited fieldwork across quarries, cement firms, public works sectors, urban plots and even construction sites. Moving beyond ‘who makes the city’, this book examines (un)inhabitability of Concrete City from an Afro-centric perspective to understand the crucial but underappreciated role of concrete in reconfiguring socio-material realities and socio-political relations. Drawing on theories of Marxist framework, postcolonial urban studies, Science and Technology Studies (STS), Actor-Network Theory (ANT) and material culture, its four chapters explore spatial flows of concrete from production to consumption in Africa in relation to other human and non-human actors to capture local socio-political, economic and environmental consequences of these new urban dynamics (p. 29). By giving voices to the subaltern, Choplin looks into hidden conflicts between the government's top-down ‘building’ perspective and urban residents’ bottom-up ‘dwelling’ perspective in West African contexts, and argues that concrete has given new meanings to the Southern urbanization different from that of Global North. Chapter 1 looks into the political economy of concrete, especially how concrete symbolizes economic transformations from European colonialism, resource boom, to contemporary Africanized construction boom. Through analysing a network of top-down forces from statesmen, businessmen, construction firms and international donors, it pays particular attention to the relationship between public and private sectors in the Africanization of concrete by Euro-African joint ventures (p. 58), as well as the emergence of local African figures who are challenging North-South relations of domination (p. 62). Chapter 2 shifts its focus to Concrete Cities in West Africa by introducing three typical models, including the ‘Premium City’ (with megaprojects in the centre and strategic places on the periphery) in Nigeria and Ghana, ‘Affordable City’ (with social housing schemes under public-private partnerships) in Togo, and ‘Low Cost City’ (with far-way suburban areas as a result of incremental urbanization) in Benin (p. 67). Through looking into how concrete is used to build both iconic projects and slums within and beyond Africa, it reveals that despite sharing capitalistic, fragmented and unequal features, they are not merely an expression of capitalism, but also the outcome of everyday processes driven by builder-inhabitants (p. 105). This explains why Chapter 3 offers a bottom-up subaltern-centric narrative on the social life of concrete by attending to the agency of city dwellers to shape living spaces of local communities and express their individual affect in urban Africa (p. 109). The widespread use of concrete, as a material, emancipatory and spiritual practice, plays a key role in binding local cultural values, gender relations, patriarchy, religions and passing wealth to next generations (p. 142). Despite the consensus of perceiving concrete as part of West African modernity, progress and cultural identity, many have turned against it as a symbol of an uninhabitable world. Chapter 4 examines socio-environmental influence on the planet of a rising global concrete industry, one of the most polluting and energy-intensive industries (p. 145). Since architects, scientists and inhabitants are turning away from all-concrete construction and experimenting with more ecological alternatives, the potential of locally-derived materials and sustainable building technologies in West Africa offers an opportunity for us to rethink cement industry and reinvent global construction culture (p. 172). This is a really ambitious book covering rich information, expansive topics and emerging urban theories, which would undoubtedly intrigue readers who are interested in Africa studies, urban studies, modern architecture, political economy, material culture, political science and STS. However, this richness sometimes makes it difficult for the author to run an extended analysis of every notion or topic. Maybe this is why Choplin leaves several open-ended and thought-provoking questions in each chapter, such as ‘what can we learn from these three urban forms’ (p. 67), ‘African architects alone cannot make a difference’ (p. 173) or ‘it is necessary to go beyond the single reading of transformations of African cities’ (p. 179), for future scholars to rethink African urbanism through Concrete City.