In this paper a brief history of desalination plants in Sicily is presented together with an in-depth description of processes and operating data, relevant to the plants actually operating on the island. 5 multi stage flash (MSF) units and one reverse osmosis (RO) plant are operating in Gela (total nominal production of about 80,000 m(3)/d), thus providing drinking water for more than 300,000 people living in the southern coast of the island. A thermal vapour compression multiple effect distillation (TVC-MED) plant (36,000 m(3)/d) is operating in Trapani and a small mechanical vapour compression (MVC) unit (5000 m(3)/d) is located in Porto Empedocle. In the oldest MSF units in Gela, several revamping actions have been done in order to maintain an outstanding efficient operation of the plant, regardless its long working history, whereas the other plants have shown some difficulties in operation. All these matters, together with an analysis of consumptions and operating costs, are critically and thoroughly discussed in the paper. Finally some proposals of new plants in severely droughty areas are given.