This chapter provides an introduction to women's health with attention to biological, psychological, and sociological aspects of women's lives. We suggest that further exploration of gender differences in symptom presentation, diagnosis, prognosis, risk factors, treatment effectiveness, and psychosocial factors for various disease entities is needed in order to enhance appropriate prevention and intervention strategies for women and their families. Specifically, we present overviews of the five leading causes of death among women (i.e., CHD, lung and breast cancer, stroke, COPD, and HIV/AIDS); the leading cause of injury to women (i.e., domestic violence); and chronic diseases common in women (i.e., arthritis, fibromyalgia, and osteoporosis). Mental health conditions prevalent among women, as well as information on the association between mental and physical health, are addressed, followed by a discussion of women in mental health treatment, health insurance, and relationships with healthcare providers. Stressful conditions related to pregnancy (i.e., miscarriage, infertility, postpartum reactions, and peripartum cardiomyopathy) are highlighted. Last, we discuss social and cultural influences on women's health focusing on the relationship between socioeconomic status, multiple roles, sex roles, and socialization as they relate to psychological and physiological illness. We conclude with the current status of women in health care and psychology and future directions in the field.