This study evaluates the differential effectiveness of six different anti-litter procedures in two neighborhood theaters. The procedures used to encourage individuals in attendance to pick up litter and deposit it properly included: providing litterbags, providing litterbags with instructions to use them, providing extra trash cans, showing a special anti-litter film before the feature film, and providing incentives for the appropriate deposit of litter. In both theaters, the incentive procedures resulted in the removal of over 90% of all litter by the children in attendance, a figure far above that achieved by the other procedures investigated.