Endobronchial brachytherapy is by far the oldest interventional bronchiological treatment procedure. In the decades following its inception in 1922, it has undergone progressive modification by innovations in radiation physics and techniques, and has enjoyed a renaissance with the introduction of fibreoptic bronchoscopy, local anaesthesia, modern afterloading devices, and high dose rate (HDR) treatment with iridium-192, an isotope with very high activity. However, there is little standardization of dose-specification, fractionation and optimal dosage using this isotope, and homogeneous, objective analyses of the clinical results of treatment using iridium-192 is lacking. Very often, the exact staging of patients is lacking. For such reasons, any evaluation of the efficacy of endobronchial brachytherapy is significantly impeded. However, reliable data are available on the palliative effect of HDR-brachytherapy, which is safe, fast in onset and apparently superior to external beam radiotherapy (EBRT) alone. In addition, some studies document the curative effects, or complications, offers not only an insight into the working principles of radiation treatment but also into the biological behaviour of bronchial tumours. Endobronchial HDR-brachytherapy should be compared to the other interventional procedures focusing on the same aim, namely that of restoring patency of a previously occluded bronchus. This is the overall challenge to pneumologists working in this field.