As intergenerational stewards of capital, pension funds can have many good reasons to embrace environmental, social, and governance (ESG) issues in their investment practices. Yet the particular structure of pension funds creates both advantages and disadvantages for the integration of ESG. This paper reviews the historical origins, regulatory mandates, and fund structures of pensions, to tease out exactly which of these characteristics enable and which of them impede the inclusion of ESG at pension funds. We use the case of PSP Investments to lend depth to the application of the strategies that emerge in the pensions industry.