Water transport in the vapor phase through a porous hydrophobic membrane has been studied in different experimental situations. Pure water and/or different aqueous solutions of sodium chloride, ranging from 0.5 to 5 mol/L, were employed on both sides of the membrane. The experiments were carried out under temperature differences varying between 5 and 30 K, and at mean temperatures varying between 20 and 40 degrees C. The stirring rate was varied between 0 and 350 rpm. The results were interpreted based on the existence of unstirred polarization layers.