Infrastructures are typically viewed as the material and social forms that allow for exchange over space: the pipes, wires, people, roads, and, in the digital age, cell towers and wireless networks, that connect villages, towns, and cities to wider national and transnational systems, and facilitate the flow of goods in both a cultural and physical sense. Infrastructures are important for social life, not only because they allow for exchanges but because they “mediate” social reality, connecting individuals and localities to wider cultural, religious, and economic networks. The articles in this special issue grew out of a workshop held at the University of Toronto in summer 2016. The cities represented in these studies—Jakarta, Yogyakarta, Semarang, and Bogor—are all on Java, although the kinds of infrastructures they highlight can be found throughout the archipelago. This collection analyzes infrastructures for mitigating urban flooding (Abidin Kusno, Lukas Ley), “escorting” migrant workers to and from their jobs in other countries (Johan Lindquist), accessing the internet (Jessika Tremblay, Merlyna Lim), moving people around cities (Sheri Lynn Gibbings et al.), handling household food waste (Tammara Soma), and informal living and working (Jan Newberry).