This study was conducted to evaluate the validity and reliability of an instrument designed to measure risk of perineal skin injury in hospitalized individuals. Interrater reliability of the Perineal Assessment Tool was examined by correlating the scores calculated by a wound, ostomy and continence nurse compared to those calculated by staff RNs and LPNs using the same tool with the same patient. Content validity was assessed by obtaining level of agreement ratings from 102 wound, ostomy, and continence nurses. Good correlation between the expert and staff nurse scores was found (r = .970, confidence intervals = 95%, P = .923 to .988 or P < .0001). Average perineal assessment tool subscale level of agreement scores ranged from 7.66 to 8.4 (range 1 = strongly disagree to 10 = strongly agree) and the median score for all subscales was 9. The results obtained are encouraging and justify additional reliability and validity studies.