The long term effect of elastic compression, with an emphasis on the changes in venous wall elasticity, was studied in 10 limbs with varicose veins. By simultaneously measuring venous volume, using the air plethysmograph (APG), and venous pressure, while the venous outflow was occluded, the pressure/volume (P/V) relationship of the venous system of the leg could be studied and the elastic modulus calculated. These measurements were performed prior to the application of elastic stockings and 6 weeks later, one day after the stockings had been removed. Statistically significant improvements were noted in the APG parameters studied and in the P/V curve derived elastic modulus calculations. The limbs could be divided into two groups based on the response of the P/V curves to elastic stockings and the severity of disease. Those limbs with milder disease tended to shift their P/V curves downward and to the right after compression (giving them a more normal pattern). Limbs with more severe disease showed evidence of a similar pattern of improvement at low but not at high venous pressures.