Urinary incontinence (UI), also known as involuntary urination, is any uncontrolled leakage of urine. It is a common and distressing problem, which may have a large impact on quality of life. It has been identified as an important issue in geriatric health care. The term enuresis is often used to refer to urinary incontinence primarily in children, such as nocturnal enuresis (bed wetting). UI is an example of a stigmatized medical condition, which creates barriers to successful management and makes the problem worse. People may be too embarrassed to seek medical help, and attempt to self-manage the symptom in secrecy from others.

Pelvic surgery, pregnancy, childbirth, and menopause are major risk factors. Urinary incontinence is often a result of an underlying medical condition but is under-reported to medical practitioners. There are four main types of incontinence:

• Urge incontinence due to an overactive bladder
• Stress incontinence due to "a poorly functioning urethral sphincter muscle (intrinsic sphincter deficiency) or to hypermobility of the bladder neck or urethra"
• Overflow incontinence due to either poor bladder contraction or blockage of the urethra
• Mixed incontinence involving features of different other types

Treatments include pelvic floor muscle training, bladder training, surgery, and electrical stimulation. Behavioral therapy generally works better than medication for stress and urge incontinence. The benefit of medications is small and long term safety is unclear. Urinary incontinence is more common in older women.