The Indian software industry is a prime example of globalisation. The industry has been characterised by large cross-border mobility of its skilled labour force. Using a unique survey of Indian software firms, our paper quantifies the extent and impact of mobility on firm behaviour and performance. Cross-border labour mobility in the paper refers to both temporary and permanent labour flows by Indian software professionals. The picture that emerges is of a highly mobile world in which temporary mobility has been an important characteristic of the industry.