This descriptive, comparative study examined the relationship between three body positions, body weight, and tissue interface pressure measurement on three support surfaces among residents who were 65 years of age or older. The support surfaces included the Sof. Care bed cushion, Biogard foam mattress, and hospital mattress. Subjects included 12 ideal body-weight and six less-than-ideal body-weight individuals from a long-term care facility in a Mid-western state. Results indicated no significant difference in sacral tissue interface difference between ideal body weight and less-than-ideal body weight subjects. However, the sacral measurements were significantly greater in the supine position than those taken in the Fowler's and semi-Fowler's positions. A significant interaction was found between position and support surface with subjects in Fowler and semi-Fowler positions on the Sof. Care Surface exhibiting the lowest mean tissue interface pressure at the sacrum.