The private sector has been active in providing and operating infrastructure to deliver water and wastewater services around the world for centuries. Over time, different business models have evolved in different countries to respond to different conditions, cultures and legal systems. This evolution is a continuous process that requires operators to adapt and innovate so that they are able to meet the needs of the people who use their services and the cities that employ them. AquaFed’s members operate a wide range of water systems in many countries. The services range from simple rural systems using low-level technology to very large and sophisticated systems that require high-tech, treatment processes, SMART networks and advanced data management. Because of the public interest nature of these services, private operators usually operate under the control of public authorities. This control takes the form of a contract or license. In addition, they are often controlled by a range of regulators that supervise matters such as costs and prices, water quality, health and safety and environmental protection.