Passport requirements vary from island to island, but visas aren't required for most nationalities.

Customs Regulations

All the Caribbean islands allow a reasonable amount of personal items to be brought in duty free, as well as an allowance of liquor and tobacco. Determining what you can take home depends on where you’re vacationing and your country of origin. Check with your country’s customs agency for clarification.

Visas

Requirements vary from island to island. Citizens of Canada, the EU and the US don’t need visas for visits of under 90 days throughout the region.