Architecture and urban planning have always been subject to, and affected by, processes of transnational cultural exchange and professional networking. Yet, the modes and geographies of knowledge mobility in urban development have matured in the last two decades, with various forces resulting in forms of transnational learning that are faster, more frequent and have more impact. The articles in this special issue provide an important contribution to understanding this maturation, and highlight the particular ways in which knowledge and practice relating to building design move from place to place. In this introductory article, we develop an analysis of how transnational building practices come to be. We highlight the way that transnational building practices can both deepen our knowledge of the constitution of knowledge mobility, and exemplify the profound tensions that result from the clash between the structuring logic of international markets and the need to adapt global ideas to local contexts. Thus, in addition to de‐naturalizing mobility and teasing out how movement is manufactured, we draw attention to the way that the inescapable relationships between buildings and markets determine the trajectories and effects of transnational knowledge networks. This opening up of the political economy of mobility, we believe, is one of the most pertinent issues in relation to considerations of mobility more broadly.