["Sociological Forum, Volume 36, Issue 1, Page 92-110, March 2021. ", "\nPublic sector employees are highly engaged in civic and political life, from voting to volunteering. Scholars have theorized that this political activity stems from “public service motivation,” or the selection of publicly oriented individuals into public work. We build on this work by analyzing the role of public sector unions in shaping participation. Unions are central mobilizing organizations in political life, and one in three public sector workers are unionized. Special supplements of the Current Population Survey provide data on various forms of participation, sector, union membership, and union coverage. Logistic regressions find that unionized public sector workers have much higher odds of engaging in a range of activities compared to non‐union public workers, including protest, electoral politics, and political communication. Union membership impacts service work to a lesser extent, suggesting that unions are more central to political lives. These findings have implications for the consequences of union decline, including the class, race, and gender composition of who participates in democratic life.\n"]