You can buy a one-way ticket or an all day/round trip ticket for Link light rail or Sounder at all Link light rail stations and Sounder stations. You can pay with cash or a credit/debit card. Of course, the easiest way to pay is with an ORCA card. It takes the guesswork out what to pay and can be used on Sounder, Link light rail, ST Express buses and several other transit agencies throughout the region.