For a lot of us, the very idea of walking up to strangers on the street and taking a picture of them is enough to bring on a cold sweat. But no other subject you will encounter will bring home the wonder and charm of far-flung places like portraits of the people who live there.
The best way to find interesting faces and characters is simply to wander where people gather: markets, fairs, city parks, and the like. In these situations, working candidly (that is, unobtrusively) is often your only alternative, as subjects come and go so quickly. A moderately long telephoto lens (an 80 mm to 200 mm zoom, for example) will enable you to remain at an inconspicuous distance, but remember there is a fine line between working politely from afar and appearing sneaky. If you are perceived as the latter, you will certainly draw more suspicion than cooperation. If you're spotted by your subject, simply smile and turn the camera away, or better yet, seize the opportunity to start a conversation in which you can ask him or her to pose.
Posing someone for a portrait isn't as mysterious or daunting as it sounds. Frame the scene tightly to take in just the head and shoulders, and try to keep direct eye contact with your subject. Don't automatically encourage people to smile: Allow them to be shy or pensive or curious. Portraits look best when the background is either simple or out of focus; one technique is to use a large aperture and selective focus to cast the background into a soft blur. Soft, even lighting is most flattering, so try also to pose your subject in the shade of a building or tree. Bright midday light from overhead is the worst; it will create strong shadows in the eye sockets (use flash fill to open them).
Finally, remember that there are places in the world where taking someone's picture is taboo. Ask at your hotel before you go out.
