B2B why do you do them?

[Putterdude]

Many b/b are not the same itinerary but may include some of the same ports of call, particularly in the Caribbean and Alaska. We like to book them early to be sure we don't have to change cabins and they are great way to take a 7 or 10 day cruise and make it a 14 or 20 day vacation. The downside is that the menu is the same on both legs and much of the entertainment tends to be repeated.

[marco]

Some folks REALLY REALLY like a particular ship, and as the above poster stated, it makes a 7 or 10 day cruise a 14 or 20 day cruise. With an entire different bunch of passengers, it can really can make a big difference in the personality of the cruise and it's more like doing two totally separate cruises, one right after the other, but on that ship that you REALLY REALLY like!