SPECIFIC AIM The deleterious health consequences of too much sitting are independent of moderate-to-vigorous physical activity. Understanding the health consequences of sitting time is particularly relevant for older adults who are extremely sedentary and at high risk of several chronic diseases that have been linked with sitting time, including type 2 diabetes. Interestingly, sedentary behavior is least studied among older adults who may benefit the most from reducing sitting time. Reducing uninterrupted sitting time in older adults is a research priority because the pervasiveness of sitting time, typically >8 hours per day, provides many opportunities for intervention. Specific interventions are required to reduce sitting because it is such a habitual behavior and is reinforced by social norms and chair-dominant contexts.