This study evaluates the usefulness of the urethral pressure profile (UPP) parameters in assessing the severity of genuine stress incontinence (GSI). Functional length (FL), maximum urethral closure pressure (MUCP), pressure transmission ratio (PTR), residual area at stress (RAS), number of patients with incontinent spikes (IS), and distribution of IS on UPP were determined in supine and standing position for 54 patients (group 1) with a 1-hour pad test < 2 g and compared with the values of 63 patients (group 2) with a 1-hour pad test > 2 g. The results were similar: FL (supine: 24 mm +/- 6/26 mm +/- 7 [P:0.2]; standing: 26 mm +/- 8/24 mm +/- 11 [P:0.5]); MUCP (supine: 51 cm H2O +/- 23/47 cm H2O +/- 20 [P:0.3]; standing: 45 cm H2O +/- 21/38 cm H2O +/- 18 [P:0.1]); and PTR (supine: 83% +/- 27/84% +/- 31 [P:0.9]; standing: 81% +/- 25 and 88% +/- 27 [P:0.3]). But the RAS was lower (supine: 502 mm2 +/- 497/246 mm2 +/- 268 [P < 0.009]; standing: 500 mm2 +/- 534/271 mm2 +/- 306 [P < 0.05]) in group 2. If the percentage of patients with IS was higher (supine: 57/93% [P < 0.001]; standing: 54/84% [P < 0.01]) in group 2, the distribution of IS over the entire FL demonstrated no differences between group 1 and 2. In conclusion, except for the RAS, standard UPP parameters cannot be considered determinant in assessing the severity of GSI.