We examine the roles of democratic politics and political institutions in shaping social welfare spending in 18 contemporary capitalist democracies. We explore the social spending consequences of government partisanship, electoral competition and turnout, and the self-interested behaviors of politicians and bureaucrats, as well as such relatively durable facets of political institutions as neocorporatism, state centralization, and traditionalist policy legacies. Pooled time series analyses of welfare effort in 18 nations during the 1960–82 period show that electoral turnout, as well as left and center governments increase welfare effort; that the welfare efforts of governments led by particular types of parties show significant differences and vary notably with the strength of oppositional (and junior coalitional) parties; and that relatively neocorporatist, centralized, and traditionalistic polities are high on welfare effort. Overall, our findings suggest that contrary to many claims, both partisan and nonpartisan facets of democratic politics and political institutions shape contemporary social welfare effort.