New treatment guidelines are required to improve the tuberculosis control strategies that have been used for 30 years. Seven centers of the Barcelona Tuberculosis Research Unit (BTRU) (Unitat d'Investigació en Tuberculosi de Barcelona) are collaborating with the Division of Tuberculosis Elimination of the United States Centers for Disease Control and Prevention in a series of clinical trials on latent tuberculosis infection and tuberculosis disease. BTRU participation began in 2004 with Study 26, an evaluation of the efficacy and tolerability of rifapentine plus isoniazid administered once weekly for 3 months compared with the standard treatment for latent tuberculosis infection. The BTRU centers together enrolled 246 patients (3% of the total). General enrollment was completed in February, 2008. HIV-infected patient and child enrollment continues. Treatment with 12 doses instead of 270 doses is expected to be a clear success. However, the analysis will be completed in 2010. Study 28 (started in 2006), designed for the treatment of pulmonary tuberculosis, compared standard treatment with an experimental regimen substituting moxifloxacin for isoniazid. BTRU centers together enrolled 15 patients (3.5% of the total). The provisional results (presented at the 47th Interscience Conference on Antimicrobial Agents and Chemotherapy in Chicago, 2007) showed no difference between the sputum conversion rate of each regimen at week 8 of treatment. Study 29 is currently underway, in which rifapentine was introduced in the experimental regimen for active tuberculosis treatment.