Specialized and multidisciplinary care is needed for patients with amyotrophic lateral sclerosis (ALS). Respiratory failure secondary to respiratory muscle dysfunction, ineffective cough, weight loss and progressive loss of autonomy should always be sought and explored. Very few tests are needed to assess a patient with ALS: spirometry, blood gases, nocturnal oximetry, cough peak-flow, and follow-up of body weight. Patients should be informed clearly as to the nature and evolution of ALS, and as to the potential benefits and disadvantages associated with each treatment modality in order to be involved in therapeutic decisions. This evidence-based review focuses on respiratory care of patients with ALS.