Biological sex, fluctuations in steroid hormones throughout life, and gender as a social concept influence all aspects of health and disease. Historically, women were excluded from research. Although great strides have been made in including women, there are still many gaps in understanding sex and gender differences in many medical conditions. This conference will discuss the importance of examining sex and gender differences in Alzheimer's disease and other age-related research at the population level. Topics covered will include sex and gender differences in risk factors, genetic predisposition, symptom presentation and clinical diagnosis. In addition, the cross-cultural and geographic effects of sex and gender differences in Alzheimer's disease will be considered.