Overactive bladder is characterized by the occurrence of increased urinary urgency, with or without urgency incontinence, usually with frequency and nocturia, with no local factors that might cause such symptoms. The aetiology of overactive bladder is not well known. In its diagnostics we use several instruments, such as patient’s history, physical examination, laboratory and imaging studies and urodynamic evaluation (which should be performed as the last one). Treatment possibilities include anticholinergic drugs, adjuvant pharmacotherapy, neurotoxins administered intravesically, surgical treatment, electrostimulation and biofeedback.