This paper proposes to use a suitable liquid desiccant to extract fresh water from the humid atmosphere. The night-time moisture absorption and the day-time moisture desorption take place in the same unit. It consists of a flat, blackened, tilted surface and is covered with a single glazing. During the night, the strong absorbent flows down as a thin film over the glass cover in contact with the humid ambient air. Due to absorption of moisture from the ambient air at night, the absorbent becomes diluted. In order to recover the fresh water from the weak absorbent, it flows down as a thin film over the absorber during the day and is heated by solar energy. The water that evaporates fi om the absorbent rises to the glass cover by convection where it is condensed on the underside of the glass cover. The absorbent leaving the unit becomes strong and ready for moisture absorption at night. The performance of the unit was computed analytically for typical summer climatic data for the month of August in Dhahran, Saudi Arabia, by solving the energy balance equations. It is shown that for the given operating conditions it is possible to obtain about 1.92 kg of water per m(2) of the unit. The influence of absorbent concentration and its flow rate on the performance of the system are briefly discussed in the paper.