A growing number of infectious complications are reported after bronchial fibroscopy procedures. The risk of nosocomial patient-to-patient or environment-to-patient infection is real via contaminated fibroscopes. Cross transmission can be caused by several microorganisms, the most frequently identified being Pseudomonas aeruginosa, Mycobacterium tuberculosis and other atypical mycobacteria. Fibroscopes can be contaminated via different mechanisms, generally related to poorly adapted cleaning and decontamination protocols. Identified errors include an insufficient cleaning phase, an inappropriate disinfecting agent (iodine derivatives, chlorhexidine), defective cleaning or disinfection of accessory equipment, or use of tap water for rinsing. Finally several episodes of Pseudomonas and atypical mycobacteria infections have been found to result from the use of automatic cleaning machines. Particular attention must be paid to the use of these devices. Official guidelines for the disinfection of endoscopic equipment must be rigorously applied in all centers. The personnel should have adequate training. It is also important to take regular samples and make regular bacteriology controls of the water and fibroscopic equipment.