Want to be the perfect international traveler? It's all about research, preparation, and planning ahead. And, we admit, these things take work. But it will all pay off when you pass the passport inspection with flying colors, arrive at your destination with all the proper vaccinations, and greet the cabbie with a friendly "hello" in his native tongue—all without batting an eye. These 11 things to know before you go will take you from last-minute mess to expert globe-trotter, all in time for your next trip.