OBJECTIVE: To determine if variations in common treatments for benign paroxysmal positional vertigo (BPPV) affected efficacy. STUDY DESIGN: Prospective, pseudo-randomized study. SETTING: Outpatient practice in a tertiary care facility. SUBJECTS AND METHODS: Patients (n = 118) with unilateral BPPV of the posterior canal, including 13 patients with BPPV of the lateral canal, were tested at a tertiary care center on one of five interventions: canalith repositioning maneuver (CRP), CRP plus home exercise, modified CRP, CRP for patients with involvement of two semicircular canals, and self-CRP home exercise. Self-CRP was also compared to previously published data on efficacy of the Brandt Daroff exercise. Main outcome measures were vertigo intensity and frequency, presence/absence of Dix-Hallpike responses, Vestibular Disorders Activities of Daily Living Scale (VADL), and computerized dynamic posturography. RESULTS: Vertigo intensity and frequency and Dix-Hallpike responses decreased significantly, and posturography and VADL improved significantly from pre- to post tests. No other significant changes were found. The groups did not differ significantly. Vertigo intensity and frequency were not strongly related at pretest but were related at post-test. Length of illness and age did not influence the results. CONCLUSION: However the head is moved, as long as it is moved rapidly enough and through the correct planes in space, repositioning treatments are likely to be effective. Therefore, clinicians have a range of choices in selecting the treatment best suited for each patient's unique needs. (C) 2010 American Academy of Otolaryngology-Head and Neck Surgery Foundation. All rights reserved.