The purpose of this study was to examine the effects of differential reinforcement of other behavior (DRO) on reducing unsafe playground behavior of young children at school and subsequently, if necessary, the additive effects of a brief time-out. The DRO procedure was effective in eliminating unsafe behavior for one of four participants. The other three participants experienced the addition of a time-out procedure in combination with DRO. The DRO + TO condition nearly eliminated unsafe playground behavior for all three participants who experienced the condition. Additionally, the addition of time-out did not negatively affect social interactions among peers or self-reported recess enjoyment for any participant who experienced time-out. Following experience with all conditions, participants selected the condition they would experience via a concurrent-chains preference assessment. All three participants selected an intervention condition at every opportunity, and two of three participants selected DRO + TO most often.