This dissertation consists of three essays that examine how access to healthcare shapes health outcomes in the United States and in developing countries. The first chapter provides the first causal evidence that mental health treatment infrastructure reduces mortality broadly. Using County Business Patterns data (1999–2016) and within-county variation, I fnd that each additional mental health treatment facility prevents 1.56 deaths per 100,000 residents from all causes annually. Facility closures increase mortality ten times more than openings reduce it, and Medicaid expansion amplifies facility effectiveness by 26 percent in high-uninsurance counties, demonstrating that insurance and infrastructure are complements rather than substitutes. The benefit-cost ratio exceeds 4-to-1, with each facility generating $11.7 million in annual net benefits.

The second chapter examines how insurance expansion affects emergency medical infrastructure, behavioral responses, and population health. Using Poisson pseudo-maximum likelihood estimation of a triple-difference design that exploits county-level variation in pre-ACA uninsured rates and state Medicaid expansion decisions, I find that Medicaid expansion increased ambulance service presence by 13.5 percentage points at the sample mean uninsured rate, whereas private marketplace expansion reduced availability by 7.4 percentage points. Insurance expansion also increased severe crashes involving airbag deployment by 5.2 percentage points, consistent with moral hazard. Despite increased crash severity, all-cause mortality declined by 0.8 percentage points, indicating that supply-side benefits from improved emergency medical infrastructure dominated demand-side costs from risky behavior.

The third chapter, co-authored with Tejendra Pratap Singh, investigates the health impacts of Nigeria’s free maternal and child health program, leveraging variation in program exposure across births to the same mother. Results show a 2.68 percentage point reduction in under-five mortality, approximately 14 percent of the pre-treatment mean, with effects more pronounced among disadvantaged populations and in areas with more healthcare services. Increased demand for preventive care likely drives the improvements, and the program prevents a child’s death at approximately 54 percent of annual household expenditure. Collectively, these essays demonstrate that the health returns to expanding healthcare access depend critically on the interaction between financial coverage and the physical infrastructure available to deliver care.