Children with juvenile spondyloarthropathy, classified as enthesitis-related arthritis (ERA) under the International League of Associations for Rheumatology classification of juvenile idiopathic arthritis, usually experience both arthritis and enthesitis. Treatment with anti-tumor necrosis factor-alpha (TNF-alpha) agents has resulted in dramatic clinical improvement. Radiologic imaging methods useful in the detection, diagnosis, and grading of arthritis and enthesitis include magnetic resonance imaging and ultrasonography. We describe the serial radiologic improvements of arthritis and enthesitis in a child with ERA in response to treatment with the anti-TNF-alpha agent etanercept.