Seventy five patients with chronic idiopathic axonal polyneuropathy (CIAP) were studied for five years. The standardised and quantified neurological examination shows that progression of CIAP is slow, and handicap, if present, is not severe. During the follow up period a definite cause of the neuropathy was found in only four patients (two hereditary motor and sensory neuropathy type 2, one sensory chronic inflammatory demyelinating polyneuropathy, one alcoholic neuropathy). At the end of the follow up CIAP was not related to malignancy or gammopathy. Routine repetition of laboratory tests was not informative and these tests should be performed on clinical grounds only.