This study describes the development and validation of a new and improved body-image assessment tool, the BIAS-BD, based on known body dimensions. The scale's construction consisted of 17 male and 17 female contour-line drawings that used known anthropometric body dimensions of shoulder, chest, waist, hip breadth, thigh breadth, and upper leg breadth. The figural drawings correspond to a series of body weights ranging from 60% below the known average to 140% above average. Differences between figural drawings represented a 5% change in body weight. Participants were 207 undergraduates, including 66 men and 141 women, who selected drawings that reflected their perceived size and their ideal size. Retesting occurred after a 2-week interval and resulted in test-retest reliability values of r=.86 for actual perceived size, r=.72 for ideal size, and r=.76 for body dissatisfaction (p<.005). There were no significant differences in reliability values between genders. Mean differences in perceived size, ideal size, and body dissatisfaction between the two test administrations were small. Concurrent validity, measured as the correspondence between perceived and reported size, was r=.76 (p<.005). Participants slightly overestimated their perceived body size, with women overestimating significantly more. Unlike existing scales, the present scale uses figural drawings based on known body dimensions and has better reliability and validity. It avoids several problems inherent in existing scales, including scale coarseness, the presence of ethnic facial and body features, and the lack of documented reliability and validity values. (c) 2008 Wiley Periodicals, Inc.