A simple and reproducible avian model of acute hematogenous osteomyelitis is described, and the natural history of the disease has been documented. Infection was induced by intravenous injection of bacteria. Chickens were killed 6, 12, 24, 48, 96, and 192 hours following bacterial inoculation, and the left proximal tibia and distal femur were removed for histologic examination. Bacterial deposition initially occurred within the growing ends of metaphyseal tunnels in the hypertrophic region of the zone of cartilage transformation in the growth plate. Bacterial proliferation occluded the vascular tunnel within 24 hours. The initial deposition of bacteria, the subsequent spread, and the nature of the inflammatory process are discussed in relation to the vascular arrangement adjacent to the growth plate. The frequent formation of sequestrum and the effect on the growth plate of an adjacent abscess is described.