張家偉充分運用英國政府關於香港前途問題的檔案，其中主要來自英國國家檔案館（The National Archives）近年公開的檔案。張家偉鍥而不捨地要求英國政府解封這些檔案，而部分檔案原本要遲至2049年才向公眾開放的。
Hong Kong is, in so many ways, unique. I know of no historical parallel where detailed provisions for the future administration of a territory have been laid down in an international treaty some ten years before they came into effect. Yet this was indeed the case with Hong Kong. The arrangements affected the lives of over 5 million people who lived there at the time and still affect well over 7 million people who live there now.
Gary Cheung has made full use of his access to the British Government records, most of which are now open to the public in the National Archives in London. Indeed, he has been assiduous in pressing for the opening of records, some of which would not otherwise have been released to the public before 2049.
The result is the most detailed account yet produced of the exchanges concerning Hong Kong between Ministers and officials in London, Hong Kong, and the British Embassy in Beijing. Not surprisingly, many different views were put forward on all sides. The great value of such a detailed account of what was discussed, and what different attitudes were portrayed, is that readers can make up their own minds about what they think of the various policy options and the polices eventually pursued. Those interested in the details of what was discussed in the long negotiations which produced the Joint Declaration of 1984, and the further detailed negotiations which took place during the years leading up to the transfer of sovereignty in 1997, will find this book a gold mine.
The one missing element is equivalent records of what was discussed and decided on the Chinese side of all these negotiations. Sadly, we may have to wait a long time for that. Meanwhile, Gary Cheung has given us an outstandingly good and detailed account of what was thought, said, and done as recorded in the British archives.
David Wilson (Lord Wilson of Tillyorn)
Former Governor of Hong Kong（1987–1992）