Abstract: A drill pipe/casing protector is mounted on a length of drill pipe adjacent to the tool joint of a length of rotary drill pipe that rotates within a well bore or a casing cemented in a well bore in which drilling operations are conducted. The drill pipe/casing protector comprises a protective sleeve preferably made from a compressible material secured to the exterior of the drill pipe to rotate with the drill pipe during normal drilling operations and to contact the casing and thereby prevent damaging contact between the rotary drill pipe and the casing. The sleeve rotates with the drill pipe during normal drilling operations in which there is an absence of contact between the sleeve and the casing, but the sleeve stops rotating or rotates very slowly while allowing the drill pipe to continue rotating within the sleeve upon frictional contact between the sleeve and the casing.