The incidence and prevalence of diaper dermatitis varies widely between published studies. It is a condition which causes considerable parental anxiety. To better understand the frequency of diaper dermatitis, treatment practices, and the current importance of previously identified etiologic factors, a questionnaire survey of parents who had children wearing diapers (n = 532) attending a large United Kingdom district general hospital was undertaken. At the time of survey, only 16% of the study population had diaper dermatitis. Forty-eight percent of the study population had never had an episode of diaper dermatitis. In a multivariate analysis, current diaper dermatitis was independently associated with four factors: presence of oral thrush, number of previous episodes, frequency of diaper changes, and diarrhea. Recurrent episodes of diaper dermatitis were associated with increasing age, lack of barrier cream use, current diaper rash, and frequency of diaper changes. In the majority of children with diaper dermatitis at the time of survey, treatment had been instituted in the community. Diaper dermatitis usually presents and is treated successfully outside the hospital setting and is not a common clinical problem in secondary care.