Tourism is the world's largest industry and with predictions it could be worth $15 trillion by the end of this decade, few countries can afford to ignore it. But reactions to hosting tourists vary enormously from place to place.
BBC presenter Ros Atkins grew up in Cornwall where his father was a fisherman and his mother a teacher. When Ros was six, his father got a job with the UN's FAO and that took the family first to The Bahamas, and then a little later to Trinidad and Tobago.
He has observed a spectrum of such attitudes in those countries - from lingering resentment towards outsiders in his native Cornwall, to an almost obsessive hunger for visitors in the Bahamas.
Trinidad is ambivalent; happy to welcome outsiders but only as equals with its own people while its sister island Tobago seems resigned to being a small player in a big game, with all the problems that entails.
So why should tourism's effects be so disparate? And what wider lessons might we draw from these countries' experiences?
To find out, the BBC packed Ros off on the trip of a lifetime - back to the places he stayed as a child with his itinerant fisherman father.
Talking to top politicians, industry leaders, and tourists themselves, sampling the blazing colour of Caribbean festivals and the chaos of drunken holidaymakers, he uncovers an industry which purports to increase understanding between peoples, but which appears to be encroaching on lives, accentuating inequalities, and straining the most cordial relations between visitor and host."
In programme one, Ros looks at how the relationship between visitor and host. In Cornwall and Trinidad locals are far more tentative about embracing the role of host than Bahamians, who seem to find no fault with it. The reasons for, we find out, cannot be easily explained away with a quick history lesson.