This chapter analyses the multifaceted impact of the arrival of thousands of refugees in Macau, showing how relief activities depended on the pragmatic interplay and cooperation of different state and non-state actors. Focusing on Chinese refugees from Shanghai and Guangdong province, and on Portuguese Eurasian refugees from Shanghai and Guangzhou, the chapter details how an unprecedented refugee influx constituted both a crisis and an opportunity for the territory’s administration, local population and the refugees themselves. These wartime refugee waves led to the emergence of a peculiar wartime cosmopolitanism in Macau, which sprang from new flows of people, capital and ideas from major treaty-port metropolises.