The relentless evolution of amyotrophic lateral sclerosis (ALS), a severe neurodegenerative disorder of the upper and lower motoneurons, leads to an increasing level of disability. Most patients, during the course of the disease, become unable to attend the tertiary clinical care center and are thus prevented from enrolling in clinical trials or benefiting from specialized care and management. The main objective of this study was to verify whether the ALS functional rating scale (ALSFRS) could be reliably administered by telephone to patients, when unable to attend the ALS clinic, or to their caregivers. ALSFRS is a validated instrument that assesses the functional status and the disease progression in ALS. We first administered the functional rating scale directly in the clinic to 30 patients, with definite or probable ALS, and to their respective caregivers, and found a very high agreement between the two groups for the total score and the majority of the rating items. Next, we showed, in both patients and caregivers, a high degree of correlation between the total score of the ALSFRS measured by telephone and that reported in the clinic. This indicates that ALSFRS is a reliable instrument for monitoring the disease progression in homebound patients, even when the person contacted by telephone is the caregiver. We also performed a telephone clinic, based on an unstructured interview, with 16 ALS patients at an advanced stage of the disease and unable to attend the ALS clinic. On some occasions, the person interviewed was the caregiver. The symptoms most frequently reported were a worsening of muscle strength, swallowing and breathing problems, constipation, and inability to clear lung secretions. Several patients asked for assistive and adaptive equipment. All patients and caregivers found the telephone clinic very useful and considered it a good complement to the management and care programme.