In recent years, deoxyribonucleic acid (DNA) probes have become available to study the epidemiology of tuberculosis by DNA fingerprint techniques. These methods make it possible to distinguish different strains of Mycobacterium tuberculosis. Currently, DNA fingerprinting is integrated with conventional epidemiological approaches to improve understanding of the spread of tuberculosis. This molecular approach has led to the investigation of a wide variety of epidemiological issues, such as adequate identification of outbreaks, tracing of nosocomial infections in hospitals, and investigation of the relative contribution of newly acquired versus reactivated infections in different populations. This paper reviews the potentials of DNA fingerprinting for studying the epidemiology of tuberculosis, and the lessons learned from this strategy. In addition, future prospects for molecular epidemiology will be discussed.