Chronic debilitating conditions are a significant burden on the health of women, in part because of longer life expectancies. More than 50 percent of U.S. adults reported at least 1 of 10 commonly diagnosed chronic conditions (arthritis, asthma, cancer, chronic obstructive pulmonary disease, coronary heart disease, diabetes, hepatitis, hypertension, stroke, and renal dysfunction) in the 2018 National Health Interview Survey, and more than a quarter of adults reported more than one such condition. These conditions include a range of diseases and disorders across the lifespan, and there are differences in both the prevalence and the clinical manifestation of chronic conditions among men and women. Some chronic conditions are specific to women (e.g., endometriosis or polycystic ovarian syndrome) while others have higher morbidity among women (e.g., heart disease) or are more common in women than in men (e.g., depressive disorders). Autoimmune diseases, arthritis, asthma, dementia, hypertension, and osteoporosis are also more common in women than in men; in fact, some autoimmune diseases have female-to-male ratios up to 6:1. Sex differences in the immune system may affect disease risk and response to preventative and therapeutic measures. Women may exhibit different symptoms of chronic conditions than men and can have different responses to medications (e.g., lower response-rate to first-line treatments). Further, the effects of hormonal changes (e.g., pregnancy and menopause) on the course of these conditions is not well understood. Gender differences in patient–provider interactions affect chronic condition diagnosis and treatment among women as well. Multimorbidity is the occurrence of two or more chronic conditions that may or may not have the same cause. Women are more likely than men to experience multimorbidity, and when they do, are more likely to have multiple organ systems involved. The initial chronic condition diagnosed and the pattern of accumulation within multimorbidity also differ by sex and gender. The additive and interactive nature of chronic conditions in multimorbidity among women are not well understood and therefore the conditions are often not adequately treated. Risk factors for multimorbidity include lower educational attainment and socioeconomic status; women of historically underrepresented populations are at additional risk. The evidence base for the prevention, diagnosis, and treatment of chronic conditions among women is underdeveloped. This is in large part because of a lack of intentional research on the health of women and an historical overrepresentation of men in clinical research. For example, clinical research traditionally has not been appropriately designed to obtain data on women (e.g., study end points and inclusion criteria); there is also limited research on femalespecific chronic conditions. A 2010 IOM report (Women’s Health Research: Progress, Pitfalls, and Promise) highlighted advancements in some area...