ROBERT Louis Stevenson may have said "to travel hopefully is a better thing than to arrive" but, to be fair, RLS never had to maintain an air of optimism at an airport. Whether sailing for Samoa or honeymooning in a derelict California mining colony, trying to deal with the horrors of modern travel bureaucracy was one adventure he fortunately never had to tackle.

The particular intricacies of the United States' immigration control have long been used as comedy fodder - and for ejecting troublesome foreigners, as when Richard Nixon attempted to ban John Lennon from the US by quashing his work visa application. Amy Winehouse and Boy George's recent visa troubles shows that does not look likely to change.

What have changed are the rules for getting into America. Travellers bound for the US under the Visa Waiver Program (VMP), which includes the UK, are now required to fill out an online "visa waiver" application prior to embarking. You will then be given an electronic system for travel authorisation (Esta) number, which you should provide at check-in at the airport. A single Esta number is good for two years, or the remainder of your passport's validity (whichever is shorter). Decisions can take up to three days, so it might be wise to apply before buying tickets. And beware of sites charging for this service; apply at esta.cbp.dhs.gov You should apply for your Esta at least 72 hours before beginning your journey and, as is increasingly common, you must fill out the form with your details online - no other method is acceptable.