The efficacy of bladder training was evaluated in a randomized clinical trial involving 123 noninstitutionalized women 55 years and older with urinary incontinence. Subjects were urodynamically categorized as those with urethral sphincteric incompetence (N = 88) and those with detrusor instability with or without concomitant sphincteric incompetence (N = 35). Bladder training reduced the number of incontinent episodes by 57%; the effect was similar for both urodynamic diagnostic groups. The quantity of fluid loss was reduced by 54%. This was greater for patients with detrusor instability than for those without it. Diurnal and nocturnal voluntary micturitions were also reduced. The effect on nocturnal micturition, however, was not observed in subjects with unstable detrusor function. It is recommended that bladder training be considered as an initial step in treatment of women with urinary incontinence. Provided prior comprehensive clinical evaluation is done, it can be prescribed without the need for urodynamic characterization.