[This post is part of my series on relationship-based organizing. A pamphlet version of this post is available for download here.]

Unions and organizing are complex things with many parts, dimensions, and dynamics. Major theories of unionism each try to build a worldview that organizes how these concepts fit together in a coherent way and that advances a particular set of union practices. The main theories on left union theory and strategy today include those of Jane McAlevey, Joe Burns, Kim Moody and Labor Notes, and reform caucus unionism. Other left unionisms, dominant at different points in US history but less prominent today, include syndicalism as practiced by the Industrial Workers of the World (IWW) and permeationism as practiced by Marxist-Leninist organizations. These theories are not static nor mutually exclusive, as they often overlap in important aspects, get mixed and matched in practice, and evolve over time.

Different unionisms will tend to weight the importance of the different aspects of unionism differently. Many unionisms tend to highlight one or two parts that are the most central, around which every other part is organized around to support and tie together. While each form of unionism is nuanced and complex, a useful way to survey the landscape of left unionisms is by showing what each one locates as its central concepts. I briefly draw out some of the main features of these union theories as well as some of the critiques of them.