Arrangements for oxygen use or dialysis can sometimes be made. With advance notice and a doctor's release, you may travel with many conditions. Remember to bring adequate quantities of any prescription medication you need, and always pack your medication in your carry-on luggage if you're flying to the ship. Make sure you check with the line again a few weeks prior to your cruise date to ensure that proper arrangements have been made. Cruise ships employ a security staff and you should report any incidents to the purser's office.
Most new ships have small safety compartments in the cabin.
Safe-deposit boxes are also available at the purser's office. It's a good idea to keep spare cash, jewelry, and personal documents in the safe. Make sure you have photocopies of passports and credit cards in case of theft. On shore, take the same precautions you would in any large city. Keep jewelry to a minimum and only carry the amount of cash needed for the day.