Mar 5, 2017 - 5:00 PM
in reply to Susanne
You have to buy a separate ticket for trains in Switzerland. If you are only planning on taking a train twice (from the airport to your destination and returning to the airport) you could buy the Swiss Transfer Ticket.
If you are planning on doing a fair bit of travel buy train and public transport while in Switzerland I would highly recommend the Swiss Travel Pass, which will cover virtually all transit in Switzerland for 3, 4, 8 or 15 days.
Read more about the passes on the links I have given you and let me know if you have further questions!