The holidays for 2021 you should book before it’s too late With travel set to make a welcome return next year, popular holiday hotspots are already getting booked up, so start planning now Keen to head off on that trip of a lifetime in 2021? Don't miss your chance It is Alfred Marshall who is usually credited with identifying the idea of “supply and demand” – the Victorian academic having explained the concept in his 1890 tome Principles of Economics. Now yes – it is possible that you will never have read a duller opening statement to a travel feature. But bear with us. This is relevant. Because rarely has there been a time when the normally simple process of booking a holiday has been as subject to Marshall’s twin financial streams as it is now – or will be in the coming months.