Created in 1935, the Canadian federal government’s Prairie Farm Rehabilitation Administration (PFRA) was active for over seven decades. An influential agency regionally, nationally, and internationally, the PFRA is often cited as being a model of effective government environmental management. Transforming the Prairies critically reconsiders that interpretation, underlining the mixed and equivocal results of its agricultural rehabilitation efforts in and beyond the Canadian Prairies. The promotion of strip farming as a soil conservation technique, for example, left crops susceptible to sawfly infestations. The PFRA’s involvement in irrigation development in Ghana increased Ghanaians’ vulnerability to various illnesses. And the PFRA’s construction of infrastructure intended to serve the public good failed to account for the interests of affected Indigenous peoples. Shannon Stunden Bower examines the intended and unintended results of agency activities in order to evaluate their ecological and social impact. She argues the PFRA was a high modernist state agency that produced varied environmental outcomes and that contributed to consolidating colonialism and racism. Transforming the Prairies affirms the need to rethink the PFRA, not only to improve our understanding of Canadian and environmental history, but also to ensure that contemporary environmental management efforts support more just and sustainable futures.