ven the nature of legislation, regulation and its application, that levels of pollution will be significantly reduced anywhere other than in countries with well developed and applied pollution control measures, despite the attempts by WTO to act as an arbiter on internal behaviours. This stresses the likely importance of developments in technology that would allow for the detection and remediation of pollution before it gets into water service systems. There will be a continuing challenge of more complex, persistent and toxic materials that accompany technological development. The other concern will be pollution arising from extreme climatic events (droughts as well as floods) or as a result of systems failure (accident or sabotage). These problems require back-up and robust responses - perhaps necessitating redundancy in water service systems, as these may be minimised but cannot be entirely eliminated. Overall, the environment is likely to be the greatest driver for adding costs to the future delivery of water services and managing the infrastructural impacts. The main factors are climate change and responses to this that may require large new infrastructure; expectations about security of quality and contaminant control to protect ecosystems; increasing uncertainties and the need to develop systems with in-built redundancy; and interactions across sectors such as water and energy. Political changes With the increasing trend towards decentralisation and more effective private sector involvement in water service provision, there will be political challenges. Many of these will be related to what the relationship between the centre and the local state is to be and how responsibilities are to be allocated. They involve accountability and governance in both the public and civil spheres. Regulatory frameworks, sets of obligations, and (especially) how the services are financed and revenue collected are all political matters. Change, however, has a tendency to be incremental and adaptive by nature in the face of inst