Tree climbing offers a safe, inexpensive adventure sport that can be performed almost anywhere. Using standard procedures practiced in tree surgery or rock climbing, almost any tree can be climbed. Tree climbing provides challenge and adventure as well as a vigorous upper-body workout. Tree Climbers International classifies trees using a system similar to that used in rock climbing. Trees are rated Class 1 through 6 depending on difficulty and height. Some equipment needed is a rope, a throw ball, a harness, and a daisy rope. Tree climbing technique differs from that of rock climbing and caving, in that it uses a direct hoisting system, which makes little or no use of the feet. The rope is the main tool used in hoisting and descending. Psychologically, tree climbing is a middle-level climbing experience, while rock climbing is a high-level climbing experience. Tree climbing offers relative safety, convenience, a live medium, various levels of difficulty, opportunities for night climbing and overnight camping, and economy of time and money. In a group climb, each tree is awarded a name by the first climber to reach the top (or by popular consent of the climbing party) and a register of names at the top of the tree is started for subsequent climbers. Prior to climbing, a tree should be inspected for such dangers as dead branches and unstable root foundations. Handicapped individuals, children, and families can engage in climbing. Tree Climbers International provides a tree climbing school, seminars, and a publication. (KS)