The 340B Drug Pricing Program was instituted to bolster the health care safety net without relying on taxpayer money. It allows participating health care facilities – most of which are hospitals – to purchase drugs filled at in-house or contracted external pharmacies at discounts from manufacturers. Hospitals argue that these discounts are critical to their provision of charity care and unprofitable service lines. However, with 340B purchases now comprising over 13% of drug sales, drug manufacturers argue that the program has grown beyond its original intent. They have responded to the rapid growth in contract pharmacies by enacting restrictions on distribution that in turn led to a flurry of lawsuits and legislative activity. Given the 340B program’s size, importance, and role in ongoing policy debates, it is perhaps surprising that it has received little attention in economics journals. Our paper reviews the literature on the 340B program, with an eye for the gaps in this literature that economics research can help fill. In particular, economists’ causal inference econometric toolkit and theoretical understanding of the role of government intervention can help improve understanding of 340B’s impacts and inform policy decisions.