I would like to pay tribute in this Preface to the distinguished contribution that Tony Crook, Emeritus Professor of Town and Regional Planning at the University of Sheffield, and one of the authors of this book, has made over the past four decades.

Tony is one of the world’s leading academic experts on private rental housing. He was awarded his first research grant on the topic in 1979, to study the impact of changes in the private rented sector on Sheffield’s inner city. This was followed up, among other projects, with a pioneering study in the mid-1980s of the changing ownership structure of the private rented sector in Sheffield. More than three decades later, he continues to research and publish on the supply side of the privately rented housing market.

I have been very fortunate to work with Tony on some of that research. He is a wonderful person with whom to collaborate: an outstanding team worker, always willing to do his share of the work, utterly reliable, meticulous attention to detail, and a rare ability to see both the wood and the trees; absolute commitment to robust research methods and to drawing conclusions and policy implications that are firmly rooted in research findings; and a deep understanding and knowledge of how private rental markets work in practice.

As well as his research on the private rented sector, Tony is one of the world’s leading academic experts on planning gain: the use of planning permission obligations to fund new affordable housing and infrastructure (land value capture). Since 2000, in collaboration with academics at Sheffield, Cambridge and the London School of Economics and Political Science, and as a sole investigator, Tony has worked on 17 research grants and commissions on planning gain. This has resulted in a prodigious volume of publications on the topic, including Planning Gain: Providing Infrastructure and Affordable Housing (2016) written jointly with the late John Henneberry and Christine Whitehead. Tony authored or co-authored six of the ten chapters in the book. It won the Royal Town Planning Institute (RTPI) Research Excellence Award in 2016. In 2020, Tony and Christine Whitehead won the Sir Peter Hall prize for the impact of their work on policy and practice.