Purpose: We investigate the association of clinical and urodynamic findings with corresponding clinical grade and possible predictors of clinical grade of multiple sclerosis (MS). Materials and Methods: A total of 90 patients, 28 to 62 years old (mean age 45.8 +/- 12.1), with the clinical syndrome of MS were consecutively and prospectively studied. All patients were subjected to detailed video urodynamic evaluation and electromyography of the external urethral sphincter. Results: Urodynamic evaluation revealed detrusor hyperreflexia in 52 patients (57.7%), detrusor external sphincter dyssynergia in 27 (30%) and hypocontractility or areflexia of the detrusor in 15 (16.6%). Residual urine varied widely from 50 to 900 ml. Decreased compliance with areflexia was seen in 5 patients (5.5%) and nonrelaxing sphincter (but not contracting) with bladder hypercontractility was noted in 9 (10%). Statistical analysis followed comparison of 2 proportions. When patients with a less severe form (grades 1 and 2) were differentiated from those with a more severe form of MS (grade 3), we observed a significant difference only in incontinence, high post-void residual, leg spasticity, urinary stones, hydronephrosis, type 3 detrusor external sphincter dyssynergia, no electromyography activity and positive sharp waves. The variables with the highest predictive value between the groups were urinary stones, sepsis, type 3 detrusor external sphincter dyssynergia and no electromyography activity of the external urethral sphincter (100%). Conclusions: Proper identification of the bladder and external urethral sphincter status, especially exclusion of detrusor overactivity or a dyssynergic response of the external urethral sphincter, will prevent complications that may result in deterioration of quality of life.