Few studies have prospectively examined the characteristics associated with worksite adoption of tobacco-control initiatives. Data were collected as part of the Community Intervention Trial (COMMIT) for Smoking Cessation, which conducted interventions in 11 communities. This smoking cessation intervention was based on community organization principles and delivered through multiple community channels, including worksites, health care providers, the media, and cessation resources. This article reports results from telephone interviews of intervention community worksites having 50 or more employees, conducted at baseline and the end of the intervention period. Among worksites that responded to both baseline and final surveys, 83% had not adopted a smoke-free policy at baseline, and 61% did not offer any cessation aid or quitting resources at baseline. By the final survey, 34% of those with no smoking ban at baseline had become smoke-free, and 36% of those offering no cessation assistance at baseline were offering cessation resources at the follow-up. The prevalence of policy adoption was higher among worksites employing more female employees and offering other health-promotion activities; manufacturing businesses were significantly less likely than businesses other than service and wholesale/retail businesses to adopt policies. Adoption of cessation programs was significantly more likely among worksites employing 100 to 249 workers, compared with those employing 50 to 99 workers; those predominantly employing men; those offering other types of health-promotion activities; and those with a higher rate of turnover. These results provide important information about the characteristics of worksites likely to engage in tobacco-control efforts. Health educators and others may choose to target those worksites most ready for adoption of tobacco control policies and programs, as indicated by these findings.