Diaper dermatitis results from the action of a number of physical and chemical factors on the skin. While its etiology is complex, there is agreement that prolonged contact between wet diapers and the skin leading to excessive hydration of the stratum corneum and reduced barrier function is a primary factor. Recent research also indicates that pH elevation resulting from ammonia production increases the probability of skin damage due to fecal enzyme activity. New diapers containing absorbent polymers blended with cellulose fluff in the absorbent core have been developed. The absorbent polymer binds fluids and controls pH in the diaper environment. To assess the effectiveness of these diapers, a clinical study was conducted with approximately 150 infants over 15 weeks, using fluff diapers and absorbent polymer diapers. The results clearly showed that the diapers with absorbent polymer provide a better skin environment than those with fluff only with respect to lower skin wetness and pH control (instrumental measurements). In addition, the clinicians' grades indicated a directional reduction in diaper rash severity.