Cruise to the warm waters of the Caribbean and surrounding territories, are among the favorite vacations for many people, with some cruise lines focusing on those destinations alone. But the increasing concern over homeland security, now means passengers from the U.S. will need passports at their ports of call, as well as on their return to America.

The Western Hemisphere Travel Initiative was implemented with the aim of providing identification for all citizens who wish to visit other countries, and a way to confirm that identification upon their return. By December of 2006, all U.S. citizens will need a passport for air or sea travel between the U.S. and Mexico, Canada, the Caribbean, Bermuda, South America and Central America.

Because it's wise to have an officially recognized form of identification, cruise passengers are advised to apply for a passport well in advance of any trip, since it can take six weeks or more to process, with the busiest season falling between January and July.

While the WHTI does not affect travel that goes directly to and from other U.S. territories such as the U.S. Virgin Islands, or American Samoa, if your cruise includes other stops, you'll be considered to have left U.S. territory, and will be asked to present your I.D. at the next port of call. For more information on the "Know Before You Go" program, visit the U.S. Customs and Border Protection website at http://www.cbp.gov/xp/cgov/travel/vacation/kbyg/