The present study was undertaken to evaluate the influence of clinical examination and complementary tests on the diagnosis of peripheral neuropathies. Most of the patients (81.8%) were submitted to laboratory tests, 47.4% were submitted to electromyography, and 22.5% to biopsy. A syndromic diagnosis was made in 99.0% of the patients, topographic diagnosis in 98.6%, and etiological diagnosis in 73.2%. An average of 4.8 tests per patient were requested and 36 of the 93 different tests always gave normal results. The importance of the findings is discussed.