Graffiti isn't just an eyesore, it also puts a major financial burden on homeowners, businesses, and governments worldwide.
One response is to paint over it when it appears, but the hunt is on for a more sophisticated solution.
Auckland designer Max Voskob is trying out a smart graffiti detection system which uses a mix of wireless sensors, cameras and machine learning to detect graffiti and tagging incidents as they happen.
He talks us through how the system works.