GIS Web Services Shafik Jiwani Orion Technology Inc., Canada Email: sjiwani@oriongis.com GUS Web Services are changing the way in which spatial data and functionality is managed, analysed and distributed. They provide opportunities that will unlock GIS functionality for a far wider audience than has hitherto been seen - creating the possibility for truly societal spatial data information networks. They also have significant benefits for data managers and developers alike, providing an environment for rapid system development and, potentially, overcoming longstanding issues of security, update and licensing. Illustrated by a series of case studies, this paper examines this rapidly evolving field, assessing current technology, opportunities and limitations.