Are you planning a trip abroad this summer? Or planning a meeting overseas? Regardless of when you're traveling or for what reason, I came across this handy guide which sheds some light on the ambiguity of tipping in foreign countries. Good information to have for your own travels or for sharing with your meeting participants. I've shortened the list to a few of my favorites, so be sure to check out the full article link at the bottom for more.

France:
Restaurants - if you see the words "service compris" on the bill, no tip is required though most locals will still leave about 10%. Tips at bars are not expected.
Hotels - Porters get 1 euro per bag; 1-2 euro for housekeeping; the concierge gets 10-15 euro for any reservation made on your behalf.
Misc - Tour guides should receive 25 euro per person per day; 10-20 euro for private airport transfers; 1-2 euro for taxi drivers.

Italy:
Restaurants - 10% is fine though most of the time tip is included in the bill. Also, don't be surprised if your tip is refused initially.
Hotels - 5 euro for porters; 1-2 euro per night for housekeeping.
Misc - Tipping is not as common in Italy as it is elsewhere. Taxi drivers or gondolieri (if you're in Venice) do not expect a tip, so whatever you are comfortable tipping (or not) is fine.

Dubai:
The government mandates a 10% charge on all hotel, restaurant and bar bills. You can add a few dirhams on top of that if you want to.
Hotels - Valets/porters receive 10 dirhams.
Misc - Going to the market? bag packers get a few coins; taxi drivers don't expect a tip but rounding the bill up to the next 5 dirham is a great gesture.

UK:
Restaurants - most gratuities are included in the bill, if not, 10-15% is normal. If you see an "optional charge" on your bill, make sure the amount fits the level of your experience and adjust it up or down if necessary.
Hotels - Porters, 1-2 pounds per bag; 1-2 pounds for housekeeping
Misc - drivers/taxis should get up to 10% as should personal guides or drivers; tipping boat tour narrators is optional.

Japan:
This is largely a non-tipping society so its possible tips will be refused. It seems the key is discretion so be sure to put the money into an envelope. Tour guides receive 2500 to 5000 yen; private drivers around 1000 yen or a free lunch; room attendants receive 5000 yen for one to two nights; round up your bill for taxi drivers.

Etiquette 101: Tipping Guide