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Dizziness and vertigo continues to be challenging diagnostic problems for general physicians and specialists. Frequently, vestibular studies and MRI are ordered prior to considering a clinical diagnosis. The purpose of this prospective study is to present the yield of MRI and vestibular studies in 100 consecutive patients referred to a tertiary neurotologic center. The average number of MRI and ENG studies per patient was 1.5 and two respectively. Only three MRI's and less than 30% of ENG tests were abnormal. The three MRI abnormalities were an acoustic tumor, a Chiari malformation, and enhancing white matter lesions suggestive of demylinating disease. The most common ENG abnormalities, after careful review of the raw data, were unilateral, or bilateral, caloric deficit and non-paroxysmal positional nystagmus. No central abnormalities were identified. None of the 100 ENG tests showed BPPN (Benign Paroxysmal Positional Nystagmus), commonly seen in patients with BPPV. Office vestibular examination showed BPPV in 20 patients and abnormal pursuit tracking in one patient. All abnormalities identified on ENG could be seen on office vestibular examination. The results of this study indicate that MRI and ENG yield in dizziness and vertigo evaluation is low. Cost effective management of these patients does not require early or frequent MRI or ENG testing. A careful history and systematic office vestibular examination should be used to establish a clinical diagnosis before diagnostic testing is considered.