This volume brings a set of key works by Elinor Ostrom, co-recipient of the Nobel Prize in Economic Sciences, together with those of Vincent Ostrom, one of the originators of Public Choice political economy. The two scholars introduce and expound their approaches and analytical perspectives on the study of institutions and governance. The book puts together works representing the main analytical and conceptual vehicles articulated by the Ostroms to create the Bloomington School of public choice and institutional theory. Their endeavours sought to 're-establish the priority of theory over data collection and analysis', and to better integrate theory and practice. These efforts are illustrated via selected texts, organised around three themes: the political economy and public choice roots of their work in creating a distinct branch of political economy; the evolutionary nature of their work that led them to go beyond mainstream public choice, thereby enriching the public choice tradition itself; and, finally, the foundational and epistemological dimensions and implications of their work