[Excerpt] In this chapter, we first present an overview of different forms of collective bargaining, looking at how institutions and models differ across countries. This is the basis for a review of research examining the integrative or efficiency-enhancing role of collective bargaining - which typically emphasizes strategic choice and mutual gains, and studies focusing on the distributional consequences of these institutions - which place more emphasis on the role of power and conflict in shaping bargaining processes and outcomes. We argue that research focusing on performance outcomes provides a useful but incomplete set of tools to analyze the form and consequences of collective bargaining institutions. These institutions have historically played a central role in redistributing political and economic power within workplaces, industries, and societies. Attention to contemporary changes in labor power can help to explain why and how this distinctive form of employee voice has been weakened within different national contexts.