The effect of cholesterol on the formation and properties of bilayer lipid membranes deposited on polyelectrolyte multilayered capsules was studied. The permeability of lipid/cholesterol coated capsules for NaCl was derived from osmotic response experiments and ranged from 1.45 x 10(-8) to 2.9 x 10(-8) m(.)s(-1), which corresponds to a lipid layer conductivity of (0.7-1.4) x 10(-8) S(.)m(-1). These conductivity values were in good agreement with the value of 0.8 x 10(-8) S(.)m(-1) obtained by electrorotation and were by 3 orders of magnitude lower than those found earlier for lipid layers on polyelectrolyte capsules in the absence of cholesterol.