According to longstanding scientific consensus, vaccines are widely regarded as playing a fundamental role in public health. Therefore, one would reasonably expect that the dynamics of vaccine production and distribution would place a premium on incentivizing robust levels of investment in vaccine development, with the allocation of resulting vaccine occurring in ways that reflect public health priorities. Yet, that is often not the case. This book examines this disjunction from the viewpoint of the laws, policies, and other market-driven forces that shape the development and distribution of vaccines. Together, these mechanisms have long led to problems of under-investment in vaccine research and production, and inequitable allocation of limited vaccine supply in ways that recurrently disadvantage lower-income populations.