To review the effectiveness of the canalith repositioning procedure (CRP) in the treatment of benign paroxysmal positional vertigo (BPPV) with a critical review of the literature and meta-analysis. Meta-analysis. Studies eligible for inclusion were randomized, controlled trials of the CRP performed on clearly defined cases of BPPV. A total of nine studies meeting inclusion criteria were identified by two independent literature searches of Medline. Treatment and control groups were compared for symptom resolution and elimination of a positive Dix-Hallpike test. Patients treated with CRP were more likely to demonstrate symptom resolution (odds ratio [OR] 4.6; 95% confidence interval [CI] 2.8-7.6) and negative Dix-Hallpike (OR 5.2; 95% CI 3.0-8.8) at the time of first follow-up. The effect of CRP for symptom improvement was strongest within the first month after treatment (OR 4.1; 95% CI 3.1-5.2) with some decline thereafter (OR 2.8; 95% CI 1.7-3.9). Conversely, the ability of CRP to produce a negative Dix-Hallpike strengthened between the first month after treatment (OR 3.0; 95% CI 1.8-4.0) and later follow-up times (OR 5.0; 95% CI 3.9-6.1). The CRP is more effective than control in resolving vertigo and positive Dix-Hallpike associated with BPPV. This finding was consistent among a variety of studies using different study designs. Untreated patients may demonstrate symptom improvement with time; however, many will continue to have a positive Dix-Hallpike when examined. Resolution of vertigo in untreated patients is therefore most likely because of avoidance of provocative positions.