In the course of chronic respiratory insufficiency, acute episodes often re
quire the use of mechanical ventilation. Failure of weaning, or worsening o
f alveolar hypoventilation, results in long term ventilatory assistance wit
h the need of overall care of the patient. The pneumologist has a key role
in the choice of indications. devices and mode of home mechanical ventilati
on. Thanks to the non-invasive ventilation with a facial or nasal mask, tra
cheostomy is less often needed. Respiratory failure due to lung restriction
is the best indication of mechanical ventilation. The results in COPD are
questionable. Whatever:er to the technique of ventilation and the underlyin
g disease, the pneumologist has to ascertain the steady state of the medica
l condition, patient and family education, anti social situation, all facto
rs to be taken into account before the patient can be discharged Knowing th
e specific needs in these patients' care, the pneumologist plays a key role
at each stage of home return and follow-up. He co-ordinates the different
aspects of pneumological care, like rehabilitation anti acute episodes trea
tment. The overall care of the patients should be improved by the developme
nt of health networks in the firm of chronic respiratory insufficiency.