This paper studies the impact of international business trips on the stock of knowledge available to an economy. It develops a theoretical model to analyse the possible effects, and presents an empirical application using productivity data for a panel of twelve Australian industries during 1991/2-2005/6. Business trips emerge as a significant source of productivity growth. As the knowledge transferred through business visits is non-rival, both countries of origin and destination can gain from the human capital of travellers. As a result, even countries traditionally disadvantaged by geography, size, or level of economic development have the opportunity to access the latest technology and information to stimulate growth.