This article examines the debate between the power resources and ‘new politics’ scholars concerning the politics of welfare state retrenchment in advanced industrial democracies. Both approaches make competing claims concerning the relevance of partisan differences in the current age of welfare reform. This article tests the new politics hypothesis that partisanship has had a declining impact on welfare politics over time through an analysis of the growth in the public share of health care spending in 18 countries from 1960 to 2000. Consistent with the new politics approach, the results reveal that the partisan character of government no longer plays a significant role in determining changes in public responsibility for health care during the new politics period. This suggests that the current period is characterised by general agreement across party lines on the broad parameters of the health care system, reducing the intense partisan conflicts of the past to debates over reform at the margins of the health care system