A survey of youth travel businesses paints a bleak post-Brexit scenario for the sector, and online travel firms are unlikely to escape the short-term confusion.
The WYSE Travel Confederation Brexit Survey talked to some 460 of its members around the globe about how the UK's decision to leave the EU will impact their business.
The topline answer is, quite a lot.
"Companies sending travellers to the UK or receiving UK travellers abroad were very pessimistic about the potential effect that Brexit could have on their business," it said.
That pessimism manifests itself in predictions of double-digit drops in trade. Firms sending people to the UK expect a 19% drop this year - businesses working with incoming tourists expect to be 18% down.
For outbound travel the drops are less severe at 12% for sending and receiving businesses.
The implications for online travel are not specifically mentioned, other than a note that confusion over visas and work permits will be a headwind for businesses who deal with these online.

"Stricter visa regulations could increase the value of agency services...Au pair businesses see this as potentially reducing direct/internet bookings."
But there are some stats that stand out in an online context, such as accommodation providers expecting a 10% drop in volumes and tours and activities tipping a 9% fall.
And seeing as the WYSE survey is talking to businesses which deal with younger folk - Millennials, digital natives, Gen Y - online players could potentially be more exposed to bigger declines than the overall market.
The top three factors affecting travel in general are identified as economic uncertainty, exchange rates and visas. The economic uncertainty will hit the propensity to travel; exchange rates will hit the cost of travel; visa changes will hit the ability to travel.
The implications of Brexit for the UK travel sector will emerge and evolve over time as the practical, economic and social changes take place. Online travel players will ride that wave along with the rest of the industry.
WYSE says that in 2015 UK travellers aged 25 and under made more than 10 million outbound trips; broadening that out to people aged under 35, the number of overseas trips jumps to more than 18 million.
The response of businesses in the youth travel sector to the short-term impact of Brexit is ominous. Many businesses will find it hard to cope with a 20% drop in volumes in a year, and the general uncertainty is likely to persist into 2017 and beyond.
Click here to see the WYSE Travel Confederation Brexit Survey in full.
NB Image by Mikhail Mishchenko/BigStock.com