As part of the National Worksite Health Promotion Survey, a representative sample of worksites across the United States with 50 or more employees was asked about the presence and types of activities they sponsor to promote smoking control. Smoking control activities were reported at 35.6% (CI 32.6-38.6) of all worksites. Among worksites with any smoking control activity 76.5% (CI 71.7-81.3) had a formal policy restricting smoking, 54.3% (CI 48.7-59.9) provided information about the harmful effects of smoking, and 49.6% (CI 44.4-54.8) made self-help materials available. Individual counseling, group classes, workshops, follow-up support and reinforcement, or special events were available at 38.3% (CI 32.9-43.7) of worksites with any smoking control activities. Frequency increased as worksite size increased, with large frequency differences between the smallest and largest worksites. Smoking policies were most often put into effect to protect the health of nonsmokers (39.1%, CI 32.1-46.1) or to comply with regulations or laws (38.2%, CI 32.2-44.2). The most frequently reported benefit to the worksite of smoking control activities was improved employee health (35%, CI 26.2-43.8). Benefits were considered to outweigh the cost of activities at 36% (CI 29.6-42.4) of worksites, although 41.7% (CI 34.7-48.7) said it was too soon to gauge the relative size of costs and benefits.