Member klee1446 recently posted the following review regarding an attempt to cruise on Ruby Princess:

"Cruise.com helped book our trip, they help fill out my mothers passport information because she was from Mexico, the young lady said she had to do the same for her mother. But never said anything about a Visa needed. When we were boarding the ship, we were informed that she could not go because she needed a visa. We could not leave our 73 year old mother in Seattle on her own, we just flew up the day before from California.

So we were told by Pablo that we lost everything we saved including the excursions we booked. We have never been robbed, but now we fell like it. Thanks Cruise.com"

Because her family didn't sail, the ratings provided in the review don't count, so we've had to delete the review to be fair to the cruise line and destinations rated. However, I wanted to share it here as their experience brings up an important reminder about Passport and Visa requirements for a cruise.

While a travel agent, cruise line or cruise advice website like us might offer guidance and assistance in meeting the necessary citizenship verification requirements for your cruise, responsibility ultimately lies with you -- the traveler -- to ensure that you've got all the necessary paperwork and met all the requirements to enter every country on your itinerary, as every person's situation is different. As klee1446's experience indicates, it's not a matter of not being able to disembark in a particular port; if you don't have the necessary documentation, you'll likely be denied boarding at the start of your cruise and will not receive a refund, and most travel insurance policies will not cover situations like this. 

So, do the necessary research, verify requirements will the embassy or consulate of each country on your itinerary, and make sure you arrive on embarkation day with the proper documents, or you just might miss the boat.