In recent years, there has been a rise in environmental consciousness and community awareness of waste disposal issues. However, discrepancies remain between people’s attitude and their behavior regarding waste disposal and recycling; commonly known as the “attitude behavior gap”. This study was designed to aid in bridging this gap by exploring how signage, incorporating psychological principles and effective sign design, can encourage people to correctly dispose of their unwanted materials. The utilization of festivals, mass gatherings and events as spaces to test the impact of pro-environmental messaging on behavior is an emerging field of research. This study investigated the role of signage in aiding attendees of the world music festival WOMADelaide to correctly dispose of their unwanted materials. To complement and support the three-bin system utilized by the waste contractors for the event, four signs were developed and tested in the catering area. These signs included a baseline sign, as well as three motivational signs containing graphics and messages, based on different theoretical positions or psychological principles. The results gained from analyzing the concealed camera footage indicated that the bins under the three motivational signs elicited a greater number of deposits. However, the waste was no better sorted than those located under the baseline sign. The findings of this study support previous research into the “attitude behavior gap” and highlight areas for future research into signage in a festival setting.