For Travel Documentation

A passport is preferred. However U.S.-born citizens can use a government-issued birth certificate + current, unexpired gov’t issued photo ID (e.g. driver license) can be used.   If that is the case, and there is a different name from birth (often by marriage), then the guest should bring a photo copy of that name change (e.g. marriage license).  It is more difficult to fly back from a foreign port without a passport, other than the that travel is exactly the same.