Book excerpt: The authors treat the interactive process between the mainland, Taiwan, and Hong Kong as a convenient organising framework to describe the economic, social, and communicative intercourse between the "core" Chinese entities -- mainly the mainland, Taiwan, and Hong Kong -- as well as the Chinese communities in other countries. The interactions between various Chinese entities are defined here as an informal, spontaneous, and interactive process incorporating a deeper cultural cohesion and a complex relationship across formal political boundaries, and sometimes well beyond official anticipation and regulation.