The need for high-quality water significantly increased during the second half of the last century. While heading towards the third millennium, an important problem is about to be solved at a near-affordable cost. The cost of desalinated water is decreasing, and this trend is continuing. Pure, high-quality drinking water is essential for day to day living, food production, better industry, and a better standard of living. The article summarizes the techniques, trends, economy, environment, energy aspects, and other significant parameters associated with the state of the art of modern desalination. Directions are shown for future research and development work for further reduction in water costs.