The Japanese have long regarded themselves as a homogenous nation, clearly separate from other nations. However, the present international reality of increased global population movement, which has resulted in the establishment both of significant Japanese communities outside Japan, and of large non-Japanese minorities within Japan, is undermining this long-standing view, and forcing the Japanese to re-conceptualise their nationality in new and more flexible ways. This book provides a comprehensive overview of these issues, examining the context of immigration to and emigration from Japan, considering the development of important Japanese overseas communities in six major cities worldwide, and the experience of six important immigrant communities in Japan, and assessing the consequences of all this for Japanese people's view of themselves as a nation.