It has been 25 years since the use of positive pressure ventilation with non-invasive interfaces became standardized. These have been 25 exciting years in which a succession of important events has significantly changed the history of pulmonology and contributed to the advancement and expansion of respiratory medicine. It is time to review the progress of non-invasive mechanical ventilation (NIMV) over this period. One important factor in success seems to be the early delivery of noninvasive ventilation during the course of respiratory failure. Noninvasive ventilation allows many of the complications associated with mechanical ventilation to be avoided, especially the occurrence of nosocomial infections. The current use of noninvasive ventilation is growing up, and is becoming a major therapeutic tool in the intensive care unit.