This paper investigates whether eco-industrial parks (EIPs) offer possibilities to implement sustainable development policies. EIPs are based upon industrial ecology principles that suggest industrial systems can operate in a similar fashion to natural ecological systems. Drawing upon a survey of all identifiable EIPs in the USA and Europe and in-depth interview surveys of 16 EIPs, the research discovered few examples of networking between firms or processes using wastes and materials recycling. Most EIPs are at a very early stage of development, where linkages are potential rather than real. The problems encountered in developing EIPs from scratch suggests that a more fruitful approach is to build upon existing and potential linkages withi...