This report describes the accuracy with which adults can recall the weights of their parents as they were 15 yr before. In 1962-65, measurements of height, weight and skinfold thickness were made in the Tecumseh Community Health Study. In 1979, 134 children of 96 mothers and 117 children of 79 fathers were asked to recall their parents' heights and weights at the earlier time and to select one of nine outline drawings, ranging from very thin to very fat, which best represented the parents at the time they were measured. The correlation between body mass index [weight in (kg)/height2 in (m)] as reported and as measured was 0.82 for mothers and 0.56 for fathers. Similar correlations were found between the selected figure and the measured body mass index: 0.74 for mothers and 0.63 for fathers. Measured values in the high range were underestimated, those in the low range were overestimated. Adding the figure selection to the report of height and weight increased the accuracy of estimation, particularly for fathers. Reports of height and weight and of figure selection were more highly correlated with measured body mass index than with skinfold thickness. None of several characteristics of the offspring had any major influence on the accuracy of their reports: age, sex, height, body mass index, skinfold thickness or the confidence of the subject in his ability to remember. Accuracy of the reports was similarly not related to age or height of the parent or to the report of the other parent's weight. We conclude that offspring reports of their parents' past weight may be a useful epidemiological tool.