I've been invited to present at a conference in Thailand. While I am not being compensated for the presentations per se, the organisers are covering my flights and 2 nights accomodation at the venue. My plan following the event was to take a holiday in Thailand, a total duration from first arrival of 4 weeks. I'm a UK national. Would this be allowable under Visa Waiver or is the fact I am presenting meaning I need a Visa of some kind? I know ordinary attendance at a conference will fall within a Visa waiver permitted activity.