THE WORST SOUVENIR you can bring home from a trip is the one you don’t know you packed: the offense you caused without noticing. Most travel mistakes aren’t malicious. They come from habits that are perfectly fine at home and quietly rude somewhere else. You can have a great time and still leave a trail of annoyed locals, damaged reefs, or a hotel room someone else has to clean up after you. So before you step out the door, here are eight dos and don’ts worth keeping in mind, whether you’re traveling locally or abroad.