Moisture-associated skin damage (MASD) is caused by prolonged exposure to various sources of moisture, including urine or stool, perspiration, wound exudate, mucus, saliva, and their contents. MASD is characterized by inflammation of the skin, occurring with or without erosion or secondary cutaneous infection. Multiple conditions may result in MASD; 4 of the most common forms are incontinence-associated dermatitis, intertriginous dermatitis, periwound moisture-associated dermatitis, and peristomal moisture-associated dermatitis. Although evidence is lacking, clinical experience suggests that MASD requires more than moisture alone. Instead, skin damage is attributable to multiple factors, including chemical irritants within the moisture source, its pH, mechanical factors such as friction, and associated microorganisms. To prevent MASD, clinicians need to be vigilant both in maintaining optimal skin conditions and in diagnosing and treating minor cases of MASD prior to progression and skin breakdown.