"Contesting Crimmigration in Post-hukou China" is an academic book that addresses the criminalization of internal migration in contemporary Chinese society. It examines how the hukou system, known as the household registration system, contributes to the perception of internal migrants as criminals. The term "Crimmigration" describes the merging of the criminal justice system with the immigration system and is analyzed in depth in this context. The book highlights key questions, such as how the construction of hukou contributes to criminalization, the impacts on the criminal justice process, and the changes in the role of hukou over time. Through interviews with various actors in the justice system in the Yangtze Delta region, the work provides a comprehensive analysis of the historical development of hukou and its function in social control. It is aimed at researchers and students of criminology interested in the topics of law, politics, migration, and citizenship in China.