In 1984, the tobacco workers' union and the Tobacco Institute, which represents US tobacco companies, formed a labor management committee (LMC). The institute relied on LMC unions to resist smoke-free worksite rules. In a review of the internal tobacco industry documents now publicly available, we found that the LMC succeeded for 2 primary reasons. First, the LMC furthered members' interests, allowing them to overcome institutional barriers to policy success. Second, the LMC used an "institutions, ideas, and interests" strategy to encourage non-LMC unions to oppose smoke-free worksite rules. While public health advocates missed an opportunity to partner with unions on the issue of smoke-free worksites during the era studied, they can use a similar strategy to form coalitions with unions.