The purpose of this technology assessment is to determine the effectiveness of air-fluidized beds (a Group 3 support surface) and Group 2 support surfaces for the treatment of Stage III and IV pressure ulcers in the home and other settings, and to compare the effectiveness of air-fluidized beds to Group 2 support surfaces. The Centers for Medicare and Medicaid Services (CMS) have divided support surfaces into three groups. Air-fluidized beds are the only devices included in Group 3. Group 2 support surfaces include powered air flotation beds (low-air-loss therapy), powered pressure-reducing air mattresses (alternating air mattresses), and non-powered advanced pressure reducing mattresses, which can be placed directly over a hospital bed frame. Group 1 support surfaces are pressure pads, certain mattresses, and overlays for mattresses (foam, water, and gel mattresses). Current Medicare policy reimburses for home use of air-fluidized beds only when the patient has Stage III or IV pressure ulcers and only after the patient has completed at least a 30 day course of conservative treatment "without progression toward wound healing." Medicare policy states that conservative treatment must include "use of a specialized support surface (Group 2) designed to reduce pressure and shear forces on healing ulcers." This technology assessment was prepared in consideration of the interests of CMS. Hence, we consider the efficacy of support surfaces in the treatment of patients with pressure ulcers, but the role of specific support surfaces in preventing pressure ulcers is beyond the scope of this assessment. This assessment also emphasizes the use of air-fluidized beds in the home setting. In regards to this latter emphasis, we also examined use of Group 2 and 3 support surfaces in hospitals and nursing facilities for evidence of efficacy that might be transferable to the home setting. However, generalization of these data to the home setting is not straightforward because treatment of pressure ulcers typically involves a variety of procedures that are essential to proper healing, but are seldom completely reported in clinical studies of wound healing. Standard care for pressure ulcers usually includes pressure relief and skin protection to prevent progression of the ulcer to advanced stages, debridement of necrotic tissue in Stage III and IV ulcers, wound cleansing, and dressings that promote a moist wound environment. The similarities in the way these therapies are provided in the hospital or nursing facility to the way they are provided in the home is uncertain.