In many European countries, the investigation, diagnosis and treatment of tuberculosis has early developed into a specialty. Two factors are responsible for this historical trend. 1: The influence of pioneer discoveries on theory and practice (Koch, Roentgen, Flügge, Ghon, Fahraus). 2: The increase of tuberculosis in 2 after-war periods of starvation that enabled specialists in well-equipped sanitariums to collect long period observations, to study localisations and differential diagnosis, reinfection and insidious onset, to improve the technic of serial films and to eliminate traditional diagnostic errors.