Overactive bladder syndrome (OAB) is a chronic condition characterised by urgency, with or without associated urge incontinence. Solifenacin succinate is a once daily, bladder selective antimuscarinic available in two doses (5 and 10 mg). The recommended dose is 5 mg once daily and can be increased to 10 mg once daily if 5 mg is well tolerated. This article presents pooled efficacy and safety data from four large, placebo-controlled, multinational phase III trials of solifenacin succinate with a total enrolment of over 2800 patients. Data from these trials show that solifenacin 5 and 10 mg once daily is significantly more effective than placebo at reducing urgency, incontinence, micturition frequency and nocturia and at increasing volume voided per micturition. Adverse events were mainly mild-to-moderate in all treatment groups. The results of these phase III trials support the use of solifenacin in the treatment of OAB.