Urethral pressure was investigated by a method which allowed simultaneous measurement of the cross-sectional area. In healthy women a pressure range of 25-140 cm H2O was recorded at one urethral site as a response to the circumstances under which the measurement was performed. The pressures obtained were related to the degree of urethral distension and to the time after the change in distension. Measuring urethral pressure at one specific degree of distension results in one specific pressure value according to the dimensions of the measuring probe. However, this specific pressure value cannot be considered to supply more information on urethral sphincter function than any other pressures included in a range which can be obtained by changing the circumstances under which the measurement are carried out. More provocative methods of pressure measurement which simulate some of the physiological conditions of the urethra may provide more information on sphincter efficiency.