We have studied associations of neurofunctional testing with other indexes of diabetic peripheral neuropathy in patients unselected for neuropathy. The tests included vibratory sensitivity (assessed with the Vibration Sensitivity Tester and the Biothesiometer) and thermal sensitivity (assessed with the Thermal Sensitivity Tester). Values for diabetic patients were markedly higher than those of control subjects. The neurofunctional tests were strongly correlated with each other. There were also significant associations between the neurofunctional and nerve conduction indexes. Asymptomatic patients had higher values than those of the control subjects for each test. When clinical and nerve-conduction criteria were a better indicator than thermal sensitivity. Neurofunctional testing appears to be useful for both the clinical and research assessments of diabetic peripheral neuropathy.