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The use of concrete is under scrutiny as it appears as one of the few human activities where the transition toward a post-carbon society is not possible unless large investments in risky carbon capture and storage are made. With current urbanization, it is also a sector that is expected to continuously grow, leading to increased resource consumption and emissions. In this review, we aim to shed light on the available solutions that can be implemented in the short and long term to reduce greenhouse gas emissions. Rather than waiting for disruptive technologies that could transform a very slow moving and risk-averse construction sector, this review focuses on the small improvements that every stakeholder involved along the value chain of concrete production and use can achieve. We stress how significant the combined effect of these marginal gains can be. By balancing societal needs, environmental requirements, and technical feasibility, the intention of this review is to show credible pathways for a transition to sustainable use of concrete. Key points• Cement usage is so massive, more than 4 billion tonnes per year worldwide, that large-scale replacement by other materials within the next decade is not possible.• Environmental impact of cement and concrete is low per unit of material, but the amount used makes the impact of the sector highly significant.• Reductions in CO 2 emissions are possible through successive improvement all along the cement and concrete value chain: less clinker in cement, less cement in concrete, less concrete in structures, and less replacement of structures.• By engaging all stakeholders of the construction sector, immediate savings of the order of 50% can be reached without heavy investment in new industrial infrastructure or modification of standards.• Research and development need urgently to be conducted for post-2050 construction to meet future emissions reduction targets. Alternative cement and faster carbonation of concrete should be explored.

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