When you meet the Companion to Clinical Neurology as an experienced neurologist, your first thought is to receive specific answers to problems in everyday practice. Typical items are updated diagnostic criteria for neurological disorders such as amyotrophic lateral sclerosis, movement disorders, or multiple sclerosis; charts covering modern clinical/molecular classifications of disease groups; and definitions of neurological terms that may be hard to differentiate for the young resident. In addition, there is also the wish to get feedback on specific syndromes named for the physician providing the first systematic description.