ted to transition and developing economies. In the case of many of the developed economies it is not the scarcity of water resources that will be the problem, as generally water stress will lessen. The balancing out of availability would need to be addressed, and this is linked to predictions of the impact of climate change on resource availability patterns. The rising standards of environmental protection and other factors will drive up energy demands, and it could well be that energy will become a limiting factor in making resources available. Security There are increasing concerns over security and terrorism in some countries, notably the United States. That country has already invested considerable sums of money researching the issue and has made budgetary provision to "harden" its water infrastructure against acts of terrorism and sabotage: USD 1.2 billion (EPA, 2005). It is noteworthy that this is less than 10% of the amount allocated to deal with the presence of lead piping in distribution systems. Concerns over vulnerability of water services infrastructure worldwide are likely to result in protection efforts in only a limited number of states that can afford to increase the robustness of their systems, such as the OECD member countries. Of greater potential influence is the security of electrical and electronic infrastructure that supports the operation of water services. The operation of water and wastewater systems relies on electricity to be able to function. Recent events in the United States have served to underline both the vulnerability and consequences of any failure of the electrical system or even shortages. It is an emerging area of concern, and at this stage the impacts are not well understood. Potentially it could drive new developments and demand for technology in decentralising schemes, and add additional system redundancy in order to increase resilience. It would also spur investment to utilise the embedded energy in water and wastewater as well as advances in new ways of pollution contro