Protecting species' habitats is the main policy tool employed across the globe in order to reduce biodiversity losses. These protections are hypothesized to conflict with private landowners' interests. We study the economic consequences of the most extensive and controversial piece of such environmental legislation in US history—the Endangered Species Act (ESA) of 1973. Using the most comprehensive data on species conservation efforts, land transactions, and building permits to date, we show evidence that on average the ESA does not affect regulated land markets in measurable and economically significant ways. We show that the Act's most stringent habitat protections lead to a slight increase in the value of residential properties on land that is just adjacent to protected areas. These findings mask heterogeneity at the species level, which we document. Further, we find no evidence of the ESA affecting building activity as measured by construction permits. Overall, even taking into account species level heterogeneity, the number of possibly negatively affected parcels is extremely small, suggesting that the capitalization of the economic impacts of the ESA through the land market channel are likely minor, despite potential delays to development through permitting, which we document. (with Maximilian Auffhammer, David W. McLaughlin, Elisheba Spiller, David L. Sunding)