Depending on the country where you’re traveling, losing your passport can be a serious inconvenience or even mean big trouble. Someone who finds it would probably want to help you out, but how? Your phone number is probably not mentioned and anyway, a finder wouldn’t call your foreign number at their expense. Sending it to your embassy also costs time and effort. And even if the finder would do that, it’s of little help because you may be hundreds of miles away from that embassy. What can you do?