Book excerpt: Economic and social difficulties at the beginning of the 20th century caused many Japanese to emigrate to Brazil. The situation was reversed in the 1980s as a result of economic downturn in Brazil and labour shortages in Japan. This book examines the construction and reconstruction of the ethnic identities of people of Japanese descent, firstly in the process of emigration to Brazil up to the 1980s, and secondly in the process of return migration to Japan in the 1990s. The closed nature of Japan's social history means that the effect of return migration' can clearly be seen. Japan is to some extent a unique sociological specimen owing to the absence of any tradition of receiving immigrants. This book is first of all about migration, but also covers the important related issues of ethnic identity and the construction of ethnic communities. It addresses the issues from the dual perspective of Japan and Brazil. The findings suggest that mutual contact has led neither to a state of conflict nor to one of peaceful coexistence, but rather to an assertion of difference. It is argued that the Nikkeijin consent strategically to the social definitions imposed upon their identities and that the issue of the Nikkeijin presence is closely related to the emerging diversity of Japanese society.