The aims of this study were to determine tuberculosis patients' treatment-seeking behaviors, to describe knowledge of TB among TB patients, how that knowledge affected their treatment-seeking behaviors, and to develop an appropriate model to strengthen the existing DOTS program. A cross-sectional study was conducted in all government TB clinics in Samut Prakan Province, Thailand during November 2005-May 2006. The triad model, which emphasizes the role of a triad of persons (the healthcare provider, the TB patient, and his/her treatment supporter), can improve patient adherence to TB treatment regimen. The results showed that only about a quarter (27.7%) of TB patients chose the hospitals with TB clinic for first treatment, while others chose alternative healthcare modes, including self-care and purchasing drugs from drugstores. The rate of successful treatment was higher for the experimental group (96.0%) than the control group (84.9%) (p = 0.057). The confirmed cure rate was also significantly higher in the experimental group (95.3% vs 78.9%, p = 0.02). The program could be utilized to strengthen the existing DOTS program.