Drawing on historical institutionalism and, more specifically, on the three above- mentioned streams of literature about business and labor power, the interaction between public and private benefits, and the role of ideas in policy-making, this paper provides a theoretically- informed account on the emergence of the Canada and the Quebec Pension Plans (C/Q.P. [...] This situation contrasts with the one prevailing in the United States, where the absence of direct federal participation in old-age assistance exacerbated fiscal problems at the state level (Quadagno, 1988), while stimulating the emergence of the Townsend Plan and other pension proposals that pressured the federal government to boldly enter the field of old-age security (Amenta, 2006). [...] In Canada, the legacy of the Old Age Pension Act mitigated the negative impact of the Great Depression on the aged and on provincial fiscal resources. [...] Such a delay occurred because the Privy Council and the Supreme Court of Canada struck down the initial legislation, a situation that compelled the federal government to bargain with the provinces in order to secure a constitutional amendment that would make federal unemployment insurance possible under the BNA.5 Consistent with the assumptions of historical institutionalism, the role of formal po [...] P. (Simeon, 1972).10 In the end, the provinces supported the compromises made by Ottawa as the Premiers felt the new federal plan was broader and gave them some institutional control over the future of the plan.