Self-built settlements on the roofs of high-rise buildings have been an integral part of Hong Kong’s history for over half a century. Rooftop structures range from basic shelters for the disadvantaged to intricate multi-storey constructions equipped with the amenities of modern life. This stunning book by Rufina Wu (architect, Vancouver) and Stefan Canham (photographer, Hamburg) is an in depth look at informal settlements built on top of other buildings in Hong Kong. It consists of 280 pages of photographs, drawings, and short interviews with the settlements’ inhabitants. Wu and Canham spent three months in Hong Kong’s Kowloon Peninsula exhaustively documenting five of these settlements. They did so without any organizational or personal contacts to people living in the settlements. They walked up the stairs of the first building and started talking to people. The result is the first book published on these communities. For the book, Wu made extensive measurements of each settlement that she converted into drawings that appear throughout. Stefan Canham took the lavish, carefully constructed photographs that you find in this book with his large format camera. The photographs are in both color and duotone. The craft of the documentation and its presentation in this volume is impeccable. There is a very brief section, only three images, of evicted settlements. The photographs here are powerful and show the erased homes and lives of people whose plight must have been very similar to the others documented in this book. The visual and oral research by Wu and Canham is anchored by an essay, “Rooftop Housing in Hong Kong: An Introduction,” by Dr. Ernest Chui. The essay lays out some of the historic and economic reasons for the existence of the rooftop settlements: various waves of legal and illegal immigration, tolerance for inadequate housing rather than spending money on public housing, critical shortage of land, and more.