Roughly 30% of adults report getting less sleep than recommended, and a similar proportion regularly experience difficulties falling and staying asleep. These sleep problems have a significant cost to health and well-being. Indeed, poor sleep is routinely associated with an increased risk for a range of negative mental and physical health outcomes, including depression, cardiovascular disease, and neurodegenerative diseases. In this colloquium, I will describe the upstream and proximal drivers of impaired sleep, as well as the downstream biological mechanisms through which poor sleep impacts disease risk.  Additionally, I will discuss pharmacological and behavioral strategies to address sleep impairments as well as policy opportunities to improve sleep at the population level.