Perineal dermatitis is a broad term used to describe skin problems in patients with urinary or fecal incontinence, particularly when these patients are managed by an occlusive containment device. It is frequently encountered in the care of patients with a primary complaint of urinary or fecal incontinence, or a chronic sacral wound. This article will review the physiology of the perineal skin, the pathophysiology of incontinence-related perineal dermatitis, and its assessment. Discussion of treatment will focus on principles for prevention and management and a review of currently available products.