Luas tickets are sold at newsagents and other shops, mostly in the vicinity of Luas stops. Joint Luas and Dublin Bus tickets can be purchased from Luas vending machines for immediate use, as well as from Dublin Bus ticket agents. Tickets bought at Dublin Bus agents must be validated on a bus before being valid for a tram (since Luas does not use ticket validation systems upon boarding the tram). Certain tickets are cheaper in shops than at ticket machines. Tickets cannot be purchased on board the trams.