Osteoporosis affects one in four women over the age of 65 and is a major cause of hip fractures that place women in nursing homes. In this study of 247 women, their knowledge of osteoporosis was assessed with the Facts on Osteoporosis Quiz. The instrument measured their responses to questions about self-care practices related to risk factors and preventive behavior associated with osteoporosis. Respondents came from occupational and primary health care settings and a health fair. The women ranged in age from 22 to 84 years. Findings indicated that the majority of women had inadequate knowledge of osteoporosis risk factors and preventive behavior.