To extend the proposed model to most community clinic settings, the investigators are demonstrating outcome effectiveness as well as cost effectiveness in relation to the costs of failing to control latent TB in this population. Public school adolescents are screened and 300 PPD positive male and female Latino youth (13-18 years) are assigned at random to either usual medical treatment, usual medical treatment plus non-directed (attention control) counseling, or medical care plus behavioral adherence counseling. Concurrently participating clinic personnel receive training in TB control.