Firstly, I would like to talk about the protocol for casual meetings.
Greeks are very welcoming and enthusiastic, they will give a very tight handshakes to show respect and thankful at the first sight. During the conversations, they always give warm smiles and keep the friendly eye contact to each other. Especially for men, they usually tap on each other’s shoulder. In Vietnam, this habit might be avoided cause of being a sign of bad luck and burden on shoulder. Greek people consider it as respect and intimate.
Next, I would like to show you about the dinning etiquette.
If you are invited for dinner at their home, you should send flower or gift before coming.
Wine is highly recommended. To show respect to the host, you should wear a courteous custom, and when arrive, don’t hesitate to make comments about their house. Greek people really appreciate other’s opinions, because they regard guest as noble.
Don’t feel bad if you come late, because in Greek time concept: 30 minutes late is considered as punctual.
During the meal, your sit will be designated by the host, and he will be the one starting the party and make a toast to everyone. The common toast is wishing each other good health.
Greek people perceive that laying elbows on table is rude and aggressive. Therefore, when holding utensils, your hands are expected to be visible above the table. Rest your wrists on top of the table. And in the end of the meal you should finish everything on your dishes.
In the next part, I would like to share some hospitality culture of the Greeks.
Your table might be shared with others if remaining space. Greeks are very friendly, so they don’t ever mind about sharing with each other, they consider it as a way of networking.
If you want to be served first, you should show respect and honor, the waiter will have rights to choose who to take care first, and you can summon them by making a warmly eye contact. Tips culture is publicly allowed. It is usually included in the bill. And finally, the inviter no matter men or woman will be assumed as the one paying the bill.
Last but not least, there is some hidden meaning of placing fork and knife in European culture. You can secretly and politely show them your comments about the meal or tell them that you finish by putting utensils.
After finish the dishes, when invited to home dinner, you should offer to clean up, they will not let you do so but they will very appreciate that. And don’t forget to send a thank postcard to the host the day after the meal.

If I have a negotiation in Greek, I will consider and remember these useful information you gave to us    Thanks a lot!  

"Don’t feel bad if you come late, because in Greek time concept: 30 minutes late is considered as punctual."  That sound great,i would get more time to prepare. Anyway thanks for your useful information