The terms ALS and motor neurone disease (MND) are often used interchangeably. ALS is the most common form of MND. ALS is a progressive neurodegenerative disorder involving motor neurones in the brain and spinal cord, which leads to progressive weakness and atrophy of the voluntary muscles without sensory deficit. The functions of the autonomic nervous system and the sphincters remain intact. There is no significant cognitive impairment. The diagnosis should be based on investigations in a neurological unit by exclusion of other diseases.