To provide the background for this issue of IJSL, this introduction focuses on the social and linguistic contexts for the contact between Putonghua and minority languages in China and raises some questions about language contact in China's language planning environment. It first examines how Putonghua rises as China's national language and to what extent it has spread throughout China in the past five decades. It then argues that it is particularly meaningful to investigate language contact and language planning from the perspective of a (managed) community second language acquisition model. The article concludes with highlights on how the contributions in this issue answer the questions on Putonghua spread and language contact in China's minority communities.