Overactive bladder (OAB) symptoms are an important cause of morbidity and interference in quality of life (QoL). This review considers the pertinent outcome measures currently in use in the evaluation of antimuscarinic therapy when used in the treatment of OAB symptoms. In particular, reference is made to the pivotal role of urgency and the difficulties associated with its assessment. The existing antimuscarinic agents are reviewed with particular reference to the third International Consultation on Incontinence committee’s deliberations on this subject. The limitations of scientifically conducted meta-analyses are discussed. The importance of head-to-head comparative studies is emphasised with particular reference to the contemporary literature base of reported studies. Future work needs to be targeted at patient-perceived outcomes, and study design should include outcome measures that are more meaningful to people, such as return to bladder control, achievement of normal micturition frequency and QoL. Persistence rates with therapy need to be evaluated, with evaluation of the particular factors of importance in influencing the variation between the drugs, and more studies of the effects of antimuscarinics are required in older people.