Science and technology spaces around the world are, simultaneously, major physical, technological and symbolic forms, key elements of economic strategy, and sites of international labour movements and knowledge transfer. They are thus the product of multiple imaginations, with multiple, potentially divergent, objectives. In this paper, we compare three international science spaces as ‘ethnoscapes’, emphasising the distinctive perceptions, cultures and identities amongst international science and technology migrants and visitors at these sites. This, we contend, sharpens a sense of the ‘international-ness’ of science spaces in various dimensions, given the particular experiences of scientific migrants and visitors moving into different nations, locations and facilities, their roles in constructing international communities, and their navigation of alternative spaces. It also offers insight into the production of contextual (rather than spatial or physical) localities, as international scientists and technologists experience and constitute larger formations, building on their perceptions of varied and interacting science ’scapes.