Claremont, California provides its citizens with a curbside recycling program. However, a procedure was needed to encourage non-recyclers to participate in the program. Based on information obtained through a literature review, a pilot program was designed using communication as a behavior change tool. To be optimally effective, the message should be vivid and personal. Therefore, citizens who already recycled were asked to approach their non-recycling neighbors. These block leaders gave a persuasive appeal which incorporated a graphic description of the amount of garbage produced annually by Californians. For example, 40 million tonnes of refuse was described as enough to fill a two lane highway ten feet deep from Oregon to Mexico. Furthermore, the average included a moderate fear appeal and gave recycling as a specific action that could solve the refuse problem. It was hoped that the block leaders would foster a norm appeal for the non-recyclers since they would identify with their near peers. Therefore, there would be social diffusion of the recycling behavior. In order to obtain objective measurements, the presence of recyclables at curbside was recorded for four weeks afterward. These data were compared to an information only group which receive the same appeal in pamphlet form.
During the 11 week post treatment phase, 28% of non-recyclers who were visited by the block leaders began recycling. In contrast, only 12% of the information only group began recycling on a weekly average.
More information about this case can be found here