Abstract A brief history of solar stills in Chile is presented. Theoretical studies of solar stills in that country are described. These deal with efficiency, thermal balance, thermal intertia, thermal capacity, thermal conductance, thermal lag and distillation lag with regard to solar irradiation maximum, and time constant. Chilean solar still designs with evaporating trays of wood, metal, cement, and plastic, and evaporating cloths of various designs have been tested by the authors. Tests were made with glass and plastic covers in the Solar Energy Laboratory of the Universidad Santa Maria (Valparaiso) and in the Atacama Desert (Quillagua). Their purpose was to make theoretical predictions of still characteristics under different environmental conditions.