An experimental investigation has been conducted to quantify the extent by which monolayers of fatty alcohols can reduce evaporation from a deep stationary water pool within a controlled environment. Octadecanol (stearyl alcohol), C17H35–CH2–OH, was chosen as the surface film and ethanol was selected to be the spreading agent. Evaporation suppression of 60 percent was achieved at a water temperature of 25°C with an air temperature of 20°C and a relative humidity of 70 percent. The experimental techniques and data have been validated by comparing the measured evaporation rates for film-free water with earlier data published by other investigators. Data for the evaporation rates of water covered by octadecanol films were correlated as a function of vapor concentration differences between the water surface and air.