The appropriate imaging for pediatric patients (ages 0-5 years) being evaluated for limping depends on the clinical presentation, specifically, the presence of signs of infection, any localization of pain, and history of or suspected trauma. Common diagnoses causing limping in children are briefly reviewed, and recommended imaging techniques are discussed, including toddler's fracture, transient synovitis, septic arthritis, Legg-Calve-Perthes disease, and osteomyelitis. The ACR Appropriateness Criteria((R)) are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.