Darkness pupil diameters, light reflexes, and redilatation times have been recorded with infrared TV pupillometry in 12 consecutive patients with systemic amyloidosis associated with sensory motor and autonomic neuropathy. Nine of the patients had AL amyloidosis, two had familial amyloidosis associated with a transthyretin abnormality, and one was untyped. The pupils were abnormal in all 12 patients. On the basis of redilatation lag without pupillotonia, six patients had bilateral Horner's syndrome and in one of them amyloid deposits were found in a sympathetic ganglion and in the attached sympathetic chain obtained at necropsy. Four patients had bilateral tonic pupils with light-near dissociation and two had abnormally small pupils with reduced light reactions which could not be characterised. It seems that in patients with systemic amyloidosis generalised autonomic neuropathy is strongly associated with pupil abnormality as shown by tonic reactions with light-near dissociation, by redilatation lag, or by reduced size in darkness.