Private policing in Hong Kong is very big business. In addition to the 30,807 regular and auxiliary officers of the Hong Kong Police, 280,030 security personnel working for 892 companies watch over our city. However, if books about the development of the Hong Kong Police are scarce, then books about the origins of private policing in Hong Kong have been non-existent until now.

Dr Sheilah Hamilton is no stranger to the Hong Kong Police. She spent 20 years in the Government Laboratory providing forensic support for the Force before moving on to private practice and academia. She is now an Adjunct Professor at the City University of Hong Kong. This book is a development of her Doctoral thesis.

"Public" versus "private" security is a perennial issue worldwide. No moderately sized, equipped and empowered police service can guarantee full security for all the community, all of the time. There always remains a role for private organisations to support the police in ensuring public safety. How these organisations operate without being ineffective on the one hand, or without abusing their powers on the other, is a fine balance. Dr Hamilton shows how this balance swung back and forth over the first 100 years of Hong Kong's development. When the police were inefficient, corrupt or simply undermanned there was more emphasis on private policing, whilst the need for efficient and trustworthy private security led to more regulation and control by the government, and often directly by the police.

There were watchmen in Hong Kong long before there were police officers. "Watching Over Hong Kong" traces the measures taken to control them from the comical attempts of the "Bamboo Ordinance" of 1844, designed to stop watchmen showing that they were awake by banging gongs and bamboo, and thus keeping everyone else awake too, through the "Baojia" system which was based on contemporary Mainland practice, to the District Watch Scheme of 1866 that survived into the 1970s. Dr Hamilton also discusses the security organisations set up by commercial "hongs" and various government departments; the Village Watch in the New Territories; and the provision of anti-piracy guards, which was regulated by the Hong Kong Police. This led to the enactment of the Watchmen Ordinance of 1928, which is the direct ancestor of today's Security and Guarding Services Ordinance.

"Watching Over Hong Kong" admirably fills a gap in the history of policing in Hong Kong. Dr Hamilton presents her story in a readable, well documented, and often amusing style. Her book is a case study in the interplay of the forces inherent in public-private policing and clearly demonstrates how the foundation stones of today's structure of public-private policing in Hong Kong were laid. It will be of great interest to police officers, criminologists and the general historian.

"Watching Over Hong Kong" will be published by Hong Kong University Press in June this year.

(Mr Peter Hunt, New Territories North Deputy Regional Commander, contributes this article.)

• English version only