Robert I. McDonald,^* Ian Douglas,^** Carmen Revenga,^*** Rebecca Hale,^**** Nancy Grimm,^***** Jenny Grönwall,^****** Balazs Fekete<sup>*******


*</sup>Robert L McDonald () is Vanguard Scientist at The Nature Conservancy. His research interests include urban growth and its implications for biodiversity and ecosystem services, energy policy and its land-use effects, and global agriculture and its impacts on the environment Address: Worldwide Office, The Nature Conservancy, 4245 N. Fairfax Drive, Arlington, VA 22203, USA. e-mail: rob_mcdonald@TNC.ORG
^**Ian Douglas is Emeritus Professor at The University of Manchester. His work focuses on the geography of access to water, for all kinds of human uses. Address: School of Environment and Development, University of Manchester, Oxford Road, Manchester M13 9PL, UK.
^***Carmen Revenga is a Senior Scientist at The Nature Conservancy. Her research focuses on fisheries and freshwater biodiversity. Address: Worldwide Office, The Nature Conservancy, 4245 N. Fairfax Drive, Arlington, VA 22203, USA.
^****Rebecca Hale is a doctoral candidate at Arizona State University. Her research interests include water use and its ecological implications in arid systems. Address: School of Life Sciences, Arizona State University, 1711 South Rural Road, Tempe, AZ 85287, USA.
^*****Nancy Grimm is a Professor at Arizona State University. Dr. Grimm's research concerns the structure and function of stream, riparian, terrestrial, and urban ecosystems in arid lands. Address: Faculty of Ecology, Evolution, & Environmental Science, Arizona State University, 1711 South Rural Road, Tempe, AZ 85287, USA.
^******Jenny Grönwall is an independent researcher associated with the Stockholm Resilience Centre. Her work focuses on social equity and justice in access to water. Address: 110 Marlyn Lodge, Portsoken St, London El 8RB, UK.
^*******Balazs Fekete is a Senior Scientist in the CUNY Environmental Crossroads Initiative. His research interests include global and regional hydrological modeling. Address: CUNY Research Foundation, The City College of New York, 160 Convent Avenue, New York, NY 10031, USA.