Don’t even think about giving the thumb’s up in Greece.

The middle finger has been around for over two thousand years. Back when the ancient Romans and Greeks used it, the gesture was meant to represent a penis, with the middle finger modeling the shaft and the knuckles on either side mimicking the testicles. Nowadays, the motion is considered a little less risqué: Flipping the bird can express anything from a person’s dissatisfaction to their punk rock spirit.

When it comes to offending people, gestures can be as powerful as words. In some cases, their visual impact makes them even more powerful. Here in the States, Disney World trains their employees to point with two fingers, as pointing with one can be considered rude in some cultures.

However, even the most experienced travelers occasionally make a faux pas. After all, languages are complex—a country’s history is even more so. But if you’re planning a visit to a foreign country and would prefer to avoid inciting an international incident, check out the following list of do’s and don’ts for global hand gestures.

Don’t do the chin flick. When traveling through Belgium, France, Northern Italy and Tunisia, avoid aggressively brushing the bottom of your chin with the front of your fingers. This is considered a dismissive gesture and will not score you any sweet dinner plans.

Do lead with a handshake. Handshake etiquette varies depending on where you’re visiting, so study up (for instance: you should make strong eye contact in Brazil, but avoid eye contact in China.) In France and sometimes Mexico, a handshake can and should be accompanied by a double air kiss.

Do make the sign for okay. This sign is not quite universal, but using your thumb and pointer finger to form a circle is considered an acceptable gesture in countries like the US, Canada, Australia and the UK. But whatever you do, don’t turn that sign upside down if you’re in Brazil—it’s a surefire way to piss people off

Don’t give a thumbs up. In America, a thumbs up signifies a job well done or a desire to start hitchhiking. But when used abroad, the gesture takes on a slightly more aggressive meaning. Avoid giving a thumbs up while traveling in Australia, Greece or the Middle East — people might interpret it as you saying “Up yours!”

Do group your fingers all together. This sign is universal, although the intent varies from country to country. In Italy, this gesture is usually accompanied by a wrist flick and means, “What do you want?” In Congo, the sign means “a little bit of something.” Egyptians use the sign to explain that they’ll only be a moment and in Turkey, the gesture signifies beauty.

Don’t do the gesture for “rock out.” You may think you’re showing how metal you are when you make a fist and point both your pointer finger and pinkie, but countries like The Baltics, Brazil, Colombia, Italy, Portugal and Spain would strongly disagree. In these countries, the same gesture is used to give a guy a heads-up about his wife’s infidelity.