Two hundred forty women were studied, who underwent symptomatological anamnesis, clinical examination and urodynamic investigations for female urinary incontinence. Our aim was to distinguish among the three main forms of incontinence (stress, urge and mixed incontinence). When only symptomatological anamnesis is considered, there is an incidence of error in nearly a third of the cases and, when further factors like menopause, prolapse and parity are considered, the incidence of error does not reduce. A correct diagnosis can be determined only by a combined use of clinical assessment and urodynamic investigations. (As regards clinical examination, a positive stress test leads to a diagnosis of stress incontinence. As regards urodynamic investigations a cystometry positive for instability of the detrusor muscle leads to a diagnosis of urge incontinence. If both clinical examination and urodynamic investigations are positive, the diagnosis is of mixed incontinence.) Our findings suggest that routinely it is sufficient to execute only cystometry among urodynamic investigations.