National Association of Street Artists : NasaUK

http://www.nasauk.org/streetArts.html :

Definition / Description

"Street arts reach the places others fail to reach: we make theatre in the street and on the pavement, we make magic in the castle or the car park, we make music around the town square or the city centre, we perform at the end of the pier or on the beach, we follow you along the prom or surprise you in the shops.