Contrary to 'greenfield' -that is, farmland, forest, or pasturelands that have never seen development (Adams & Watkins, 2002) -the concept of brownfield seems to have two main derivations, from United Kingdom (UK) and United States (US) planning strands. On one hand, the Article 55 "Meaning of development and new development" of the UK Town and Country Planning Act 1990 defined brownfield as previously developed land that is currently not in use (Alker et al., 2000). On the other hand, the United States Environmental Protection Agency's definition incorporated the contamination of land -"abandoned, idled, or under-used industrial and commercial facilities where expansion or redevelopment is complicated by real or perceived environmental contamination" (Johnson, 1996) -which implied that all brownfields are contaminated. Contaminated or not, since the early 1990s many studies have tried to identify the main features of brownfield sites through a wide range of definitions, interpretations, and perceptions, as well as to propose different typology according to criteria of localization and purpose (Alker, 1998; De Sousa, 2008;Hollander et al., 2010). Nevertheless, little attention has been paid to the meaning of brownfield in terms of 'infrastructure' in the urban environment.The exploration of the meaning of 'brownfield infrastructures' may be an innovative way to understand how different types of abandoned infrastructures can enable urban transformation processes. In order to do this, it is necessary to also examine the notion of infrastructure and, more generally, the relationship between infrastructure and the development processes. The definition of infrastructure -that is, the basic systems and services that are necessary for a country or an organization to run smoothly, such as buildings, transport, and water and power supplies (Vitiello, 2017, 325) -goes beyond the engineered systems that provide energy, information, irrigation, sanitation and water. This definition also covers facilities -such as barracks, hospitals, and schools -and utilities such as electric, gas, telecommunication, wastewater, and water, along with streets, railway roads and highways. Infrastructure may be hard or soft 1 and works at many scales, from decentralized solar systems to highly organized global networks, such as logistics and shipping. Its meaning has recently been extended to digital infrastructure in reference to computer systems and the internet (Halegoua, 2020).Infrastructure systems have largely shaped and reshaped urban form and urban life over time, being key innovators in planning (Neuman & Smith, 2010). Communication, energy, transportation (including ports) and water and waste man-This is a draft chapter. The final version is available in: M. Finger, Y. Numan (Eds.) The Elgar Companion to Urban Infrastructure .