Objective: To evaluate and compare the efficacy of pharmacological and nonpharmacological treatments of fibromyalgia syndrome (FMS). Methods: This meta-analysis of 49 fibromyalgia treatment outcome studies assessed the efficacy of pharmacological and nonpharmacological treatment across four types of outcome measures--physical status, self-report of FMS symptoms, psychological status, and daily functioning. Results: After controlling for study design, antidepressants resulted in improvements on physical status and self-report of FMS symptoms. All nonpharmacological treatments were associated with significant improvements in all four categories of outcome measures with the exception that physically-based treatment (primarily exercise) did not significantly improve daily functioning. When compared, nonpharmacological treatment appears to be more efficacious in improving self-report of FMS symptoms than pharmacological treatment alone. A similar trend was suggested for functional measures. Conclusion: The optimal intervention for FMS would include nonpharmacological treatments, specifically exercise and cognitive-behavioral therapy, in addition to appropriate medication management as needed for sleep and pain symptoms.