Since the turn of the century, the role of business has been raised to the forefront of scholarly interest in the development of the welfare state. For the last fifteen years, this research agenda has fueled an intense debate over the nature and extent of business influence over the development of social policy. At the center of this debate stands the claim that business groups have played a more important and more constructive role in the postwar expansion of public social programs than previously realized. Other writings have raised doubts about these claims or questioned them outright. This session engages in this debate in two different ways. First, we follow recent studies that have emphasized the need for more longitudinal studies that are able to capture to what extent business attitudes towards welfare reform have been subject to change over time. Second, we aim to investigate the development of policy areas (e.g. active labor market policies, family policies, employment protection legislation, and occupational pensions) that have a particularly strong impact on the labor market and private investment. The session systematically addresses to what extent diachronic and cross-national differences in business attitudes can be explained by the institutional features of business interest groups, the political strength of pro-welfare actors, as well as the precise nature and resulting consequences of social policy reforms.