I have gone on several Eastern Caribbean cruises, and US currency has in the past always worked for almost everything. In fact, I cannot remember it NOT being ok, and that goes for cabs also. On another point, as one of our Captains told the entire ship at muster, DO NOT BE LATE RETURNING TO THE SHIP, or you will become that nation's newest citizen. To MY knowledge, the ONLY time that the ship will wait for you is if you are on an excursion planned and run by the ship line; only then will the ship wait for you to return. Some of the other moderators heere will correct me if I'm wrong.