Despite all the efforts, human and technical, put in the fight against tuberculosis, it continues to claim millions of lives every year. The emergence of forms resistant to antibiotics, particularly multidrug resistant and extensively resistant tuberculosis, is now a global threat. On the other hand, opportunistic infections caused by other species of mycobacteria, with a significant impact on immunocompromised patients, increase. This course addresses the most significant aspects of tuberculosis and other mycobacterioses, including their laboratory diagnosis and clinical application.