i am finding the website confusing. Will the Discovery pass work if Iam not flying domestic in Thailand. My route is Bangkok to Siem Reap to Luang Prabang back to BK . Do I have to know the exact dates before I book, can dates be changed. Any advice to the cheapest way to fly? Thanks in advance.

The Discovery Pass (which is on Bangkok Air, not Thai Air) is the cheapest way to fly this route. Dates can be changed, but only if there are Discovery Pass seats available. Between Siem Reap and Luang Prabang, you fly Lao Air, which is included in the Discovery Pass. Knowing all of your dates before you book is the most efficient way to book.

Thank you,

What we did when we used Discovery Pass was to look up the flights on the dates & times we wanted. Then we emailed our itinerary to Discovery Pass. One of our flights was not available anywhere close to the time we wanted so we ended up changing our schedule a bit. We booked a good 6-7 months in advance. There was also a charge for changing flights after they had been booked. This was a couple years ago, so not sure what they do today with charging.
This thread has some good info on Discovery pass.
http://www.fodors.com/community/asia...ry-airpass.cfm

We just booked discovery pass. We called the NYC office and they wee very helpful and nice. We told them what we wanted and they sent an itinerary and we were booked. Simple and easy. Maggie is the woman that helped us.

Great! Glad you got it booked.