Though diagnosis of myelopathy can be easily made by history and neurological examination, modern technologies, such as MRI and evoked potential study (EPS), have played an important role in making the anatomical and pathological diagnosis of myelopathy. To assess the accuracy of clinical diagnosis and the role of the laboratory studies, we prospectively studied 26 patients with myelopathy, admitted to S.N.U.H. We tried to decide, by clinical history and examination, the anatomical location and the pathological diagnosis, and compared them with final diagnosis. 1. The final diagnosis could be made in 23 out of 26 patients. 2. Of 17 patients with the initial clinical diagnosis of intramedullary lesion (IML), two patients turned out to have extramedullary lesions (EML). Final diagnosis could not be made in three patients, and imaging studies and EPS didn't reveal definite local lesions. In another group of nine patients with the initial clinical diagnosis of EML, three patients had IML. 3. The clinically suspected levels of lesions were shown to be accurate within one level in 20 out of 26 patients after MRI. 4. Clinical diagnosis was accurate in 18 out of 26 patients. 5. Among the laboratory tests, MRI helped localize the lesions and make the final diagnosis. EPS was most helpful in making a diagnosis of multiple sclerosis by finding out asymptomatic second lesions. Even with thorough work-up the etiologies of myelopathy in three patients could not be elucidated. 6. Review of wrong diagnosis showed that diagnostic errors were attributed to incomplete history taking or examination, misinterpretation of clinical data, and unusual presentations or unsuspected rare diseases. Therefore, the authors conclude that the physician's clinical examinations in the diagnosis of neurologic diseases are still valuable despite the technology of the laboratory studies is developing further in present days.