Bronchoscopy is a highly versatile technique in the context of intensive care and has many potentially valuable indications. Safety is of paramount importance and the risks in critically unstable patients are correspondingly greater than in more stable children. The main contraindication to bronchoscopy is if it will provide no useful information. The procedure is obviously more risky in children with severe hypoxia, uncontrolled bleeding diathesis, cardiac failure or severe pulmonary hypertension. Monitoring should include at least oxygen saturation, blood pressure (ideally by continuous, invasive monitoring) and preferably capnography. Indications for bronchoscopy in paediatric intensive care include endobronchial toilet, sometimes instilling recombinant human DNAase even in children who do not have cystic fibrosis; checking tube patency and position; assisting in a difficult intubation or tube change; achieving the selective intubation of a main bronchus; the diagnosis and management of ventilator-associated pneumonia or the ventilated, immunocompromised host; the assessment of lobar collapse or focal hyperinflation; airway stent assessment; assessment of stridor on extubation and the diagnosis of any associated disease. New iatrogenic complications are also likely to be discovered. The procedure is very safe if performed by experienced operators with back-up from doctors skilled in airway management and the monitoring of sick children.