Quantitative (not qualitative) studies were sought investigating whether horseback riding used as therapy improves gross motor function in children with cerebral palsy (CP). Eleven published studies on instructor-directed, recreational horseback riding therapy (HBRT) and licensed-therapist-directed hippotherapy were identified, reviewed, and summarized for research design, methodological quality, therapy regimen, internal/external validity, results, and authors'conclusions. Methodological quality was moderate to good for all studies; some studies were limited by small sample size or lack of non-riding controls. HBRT improved gross motor function in five of six studies (one study was inconclusive); hippotherapy improved gross motor function in all five studies. The studies found that during HBRT and hippotherapy: (1) the three-dimensional, reciprocal movement of the walking horse produced normalized pelvic movement in the rider, closely resembling pelvic movement during ambulation in individuals without disability; (2) the sensation of smooth, rhythmical movements made by the horse improved co-contraction, joint stability, and weight shift, as well as postural and equilibrium responses; and (3) that HBRT and hippotherapy improved dynamic postural stabilization, recovery from perturbations, and anticipatory and feedback postural control. The evidence suggests that HBRT and hippotherapy are individually efficacious, and are both medically indicated as therapy for gross motor rehabilitation in children with CP. Recommendations for future research are discussed.