 SMP-986 is a compound being developed for the treatment of overactive bladder syndrome OABS. This clinical study is designed to test the hypothesis that SMP-986 at doses of 20mg, 40mg, 80mg or 120mg provides greater symptom relief in OABS compared to placebo. The hypothesis will be tested by measuring the change in mean voids24 hrs after treatment with SMP-986 compared to placebo, as well comparing the change in: the severity of urgency episodes, mean number of urgency episodes24 hr, mean number of incontinence episodes24 hr and the mean void volumevoid between SMP-986 and placebo. 