Transforming the Prairies proposes a new understanding of Canada’s Prairie Farm Rehabilitation Administration (PFRA), complicating common views of the agency as a model of effective government environmental management. Between 1935 and 2009, the PFRA promoted agricultural rehabilitation in and beyond the Canadian Prairies with mixed and equivocal results. 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 the local population’s vulnerability to various illnesses. And PFRA infrastructure construction intended to serve the public good failed to account for the interests of affected Indigenous peoples. The PFRA is revealed as being a high modernist state agency that produced varied environmental outcomes and that contributed to consolidating colonialism and racism. This investigation affirms the importance of engaging historical perspectives to help ensure that contemporary environmental management efforts support more just and sustainable futures.