Three experiments were conducted in which a school principal implemented behavior modification programs with elementary school children. The behaviors dealt with were tardiness, absenteeism, and disruptions. Treatment conditions consisted of the principal: delivering tokens with monetary back-ups; assigning tasks; and engaging in activities with the children. In Experiments I and III returning to baseline conditions revealed that the principal was controlling the behaviors in question. In Experiment II a multiple-baseline design provided evidence that the principal was responsible for the observed increases in school attendance. AU three experiments resulted in changes in the Ss’ behavior in the desired direction.