Tuberculosis is often a difficult infection to treat. This review article summarizes the many manifestations of the disease and the major treatment options in the various contexts in which the disease occurs. Tuberculosis, a scourge since prehistoric times, affects more than 9 million people and causes the death of 1.5 million people each year. Effective treatment has been available for 60 years, but such treatment takes at least 6 months, and resistance to the drugs, which is increasing throughout the world, threatens the effectiveness of treatment. 1 This review summarizes the theoretical principles of tuberculosis treatment, current therapeutic approaches, areas of uncertainty, and persistent challenges. Principles of Tuberculosis Treatment A series of clinical trials conducted by the U.K. Medical Research Council and the U.S. Public Health Services between 1948 and 1986 showed that . . .