Part of this book is based on my D.Phil. thesis, which was submitted to the Department of Sociology, University of Oxford in 2014. I am grateful for the guidance and support from my doctorate advisor Professor Federico Varese, who never fails to offer unfailing support on my research. I am also thankful for Professor Lo Tit Wing for offering me advice, guidance, and support since my days as a doctorate student, and to my colleagues on the Criminology and Sociology team at the City University of Hong Kong. I am indebted for the never-failing support from my mentors Professor Eric Chui and Professor Ray Yep. In particular, this book would not have been possible but for the support shown by Professor Rob White, and Miss Helen Steadman and Miss Amy McLean for their professional top-notch editing and proofreading services. I would also like to thank Miss Annie Wong On Ling and Miss Yu Hanting for their unfailing technical support. My former research assistant Miss Lee Chee Yan has gone beyond the call of duty to assist me with this book. The Netherlands Institute for the Study of Crime and Law Enforcement and the Royal Netherlands Academy of Arts and Sciences has offered me generous support during my term as a Visiting Professor in the Netherlands, where I finished my final revisions for the manuscript.