Although worksite smoking restrictions have become increasingly common in recent years, organized labor has generally not been involved in the adoption of these policies; some evidence suggests that unions often oppose the adoption of worksite smoking policies. To contribute to an understanding of labor's role in tobacco control policies, this paper reports the results of a review of 85 arbitration cases and 5 cases of unfair labor practices charges published between 1986 and 1994. In most of the cases reviewed, management unilaterally imposed a new smoking policy, which the union then grieved. Union opposition to the policy generally focused on the process by which the policy was adopted, rather than the content of the policy; the concern was that management had breached its duty to bargain with the union regarding the adoption of the policy. These results underline the importance of joint labor-management actions on worksite tobacco control policies.