Overactive bladder (OAB) is a medical condition with the symptoms of urinary frequency and urgency, with or without urge incontinence. Traditionally, epidemiologic studies have focused on the symptom of incontinence, and therefore the prevalence and clinical impact have been grossly underestimated. Recently, several population-based studies have been conducted that have provided insight into the true magnitude of OAB. This article will review the latest data on the prevalence of OAB and discuss the impact of the condition on quality of life. Furthermore, it will examine some of the comorbidities associated with OAB and look at the potential economic impact of OAB.