Montrose Madison Wolf, who discovered the reinforcing power of adult attention for children and based on that discovery invented and named the nonviolent parenting procedure time-out; who discovered that absent speech and social development could be artificially created with operant conditioning techniques; who first engineered a token economy into a useful motivational system; who invented the good behavior game; who orchestrated the massive research program that developed and refined the Teaching-Family Model as a residential treatment solution for delinquent development; who reinvented field observation, repeated measurement, and single-subject research methods; who introduced and named the concept of social validity; and who led the founding of the discipline of problem-solving real-world research called applied behavior analysis, died of Huntington's disease on March 19, 2004, at his home in Lawrence, Kansas.