William Hillcourt, known within the Scouting movement as "Green Bar Bill", was an influential leader in the Boy Scouts of America (BSA) organization from 1927 to 1992. Hillcourt was a prolific writer and teacher in the areas of woodcraft, troop and patrol structure, and training; his written works include three editions of the BSA's official Boy Scout Handbook, with over 12.6 million copies printed, other Scouting-related books and numerous magazine articles. Hillcourt developed and promoted the American adaptation of the Wood Badge adult Scout leader training program.