This book is a product of a research project funded by the British Arts and Humanities Research Council (2013–2016). Initially, the Principal Investigator was Mark J. Cartledge (practical theology and Pentecostal and Charismatic studies) and the Co-Investigator was Andrew Davies (biblical studies and the public understanding of religion), but they swapped roles after just a year, because Mark moved to live and work in the USA. However, Mark continued to lead on the book side of the project. All of the empirical data for the project was gather by two research fellows, Sophie Bremner (anthropology) and Sarah Dunlop (practical theology) during the funded research period. They were joined by Heather Buckingham (sociology and social policy) to work on the impact side of the project. Thus the five of us comprised a multi-disciplinary research team. We want to acknowledge the support we received from the University of Birmingham, UK as well as the support that Mark received from Regent University during the course of this research period. He benefitted from the support of two Graduate Assistants during this time: Vince Le and Enoch Charles, to whom he is most grateful. A Graduate student, Jerry Brown, also assisted Mark with the production of the bibliography and the indices towards the end of the project.

The writing of the book has taken longer than anticipated due to various personal factors. Nevertheless, we are grateful for its completion and hope it will be significant for scholarship and in particular megachurch studies. We would all like to thank our families and friends for their love and support. As all researchers and writers know, the work that we do would not be possible without the encouragement of others. In particular, Mark would like to thank Joan and Becky, for the many conversations on the subject of megachurches. Sarah would like to thank her supportive husband, Andrew, particularly for Sundays when he managed to lead a church plant and keep small children alive while Sarah visited churches in London. Heather would like to thank John and Sue, her parents, for their continued encouragement, patience, and kindness; and Ricky, Hilary, Juliet, Mari, and Glenys for their listening, laughter, and support. Sophie would like to thank the leadership and congregations of Kingsway International Christian Centre, New Wine Church and Jesus House for All Nations for offering a warm welcome and participating in the research project. She also thanks her husband Robert, and Eshe and Daniel for their positivity and support.

In terms of the writing of this book, different chapters were written either by individuals or by a combination of two people. The authors of the chapters are as follows: Chapter 1 (Mark and Sarah); Chapter 2 (Mark); Chapter 3 (Mark and Heather); Chapter 4 (Sarah); Chapter 5 (Mark and Sophie); Chapter 6 (Mark and Sarah); Chapter 7 (Mark); Chapter 8 (Mark and Heather); and Chapter 9 (Mark). Mark edited the whole manuscript once the individual chapters were completed. Sarah commented on the manuscript as it was near completion and Heather proofread a portion of the manuscript.

We need to acknowledge the previous publication of some material contained in this book. Part of Chapter 3 is printed from ‘Public Theology and Empirical Research: Developing an Agenda’, International Journal of Public Theology 10 (2016), pp. 145–166 (specifically pp. 146–154) by Mark J. Cartledge, with permission from Koninklijke Brill NV, Leiden, The Netherlands. Copyright © 2016 Koninklijke Brill NV, Leiden, The Netherlands.

Finally, it is worth noting that we have followed British spelling conventions in the main text of the book. However, where American spelling has been used in the titles of books and journal articles, we have followed the original spelling convention in the references and bibliography.