This dissertation consists of three chapters that are tied together by their study of pricing mechanisms in the context of Environmental and Natural Resource Economics. The first chapter investigates the efficient pricing of carbon emissions under two non-environmental market distortions: market power and distortionary taxes. Also concerning carbon emissions, the second chapter examines how optimal carbon prices change in response to uncertainty about climate tipping consequences. Lastly, the third chapter switches the focus from efficiency to equity; it provides a quantification of water affordability concerns in the United States and studies policy options to alleviate the burden of unaffordable water services on low-income households.