BACKGROUND Acute respiratory insufficiency (ARI) with alveolar hypoventilation or incapacitating dyspnoea but without peripheral muscle involvement can be an early manifestation of respiratory involvement in amyotrophic lateral sclerosis (ALS). Some of these patients benefit from assisted ventilation. The object of this study was to analyse the results of long-term mechanical ventilation (LTMV) in ten patients with ALS. METHODS A retrospective analysis of intensive care unit (ICU) or ambulant patients with ALS who underwent LTMV in a conventional hospital ward was performed. Erect and supine spirometry, blood gas analysis and pulse oximetry were performed before the start and during the course of ventilation. RESULTS Ten patients on LTMV were included. Four from the ICU were ventilated via tracheostomy, and six ambulant patients had non-invasive (nasal) ventilation. In all cases, ventilation was performed in a conventional hospital ward. The ambulant patients improved symptomatically during ventilation, confirmed by measurement of gas exchange and of SaO2 by continuous pulse oximetry. Three of the ten patients survive in long-term care--two with nasal and one with tracheostomy ventilation. CONCLUSIONS LTMV outside ICU was possible in ten patients, seven of whom returned home. Returning home is very difficult for patients dependent on a ventilator who lack family support.