A marriage license is required in Jamaica to get married. If your wedding planner is not taking care of this for you, it is relatively easy to do on your own (we did most of this ourselves).
You need a government-issued photo ID, passports are especially acceptable if one member of the couple lives abroad. Take these to the Ministry of Justice's office at the South Tower of NCB Oxford Road (same place where you pay the fees for the PCC, but the other building), and ask the receptionist for a wedding license package. She will give you the package and explain (hopefully you get the same one I did, a lovely and helpful young lady).
There is a declaration (the white piece of paper) that needs to be signed by bride and groom in front of one witness and a JP. The witness needs to be someone personally acquainted with bride and groom. DO NOT write anything on the Minister's License! (The fancy cream paper that looks like a certificate). Take the signed and witnessed declaration along with the Minister's License and the fee of $4,000 downtown to the Government Stamp Office on East Street, pay the fee and get the receipt and give them the Minister's License to be stamped. When you get back the receipt and the stamped Minister's License, take these back to the MoJ office, and give them to the receptionist with the IDs. She will tell you when to return to collect the completed license and your IDs. Usually they turn them around in one business day. If you drop it off early in the morning, sometimes you can get them back the same afternoon.
The completed Minister's License allows any licensed marriage officer to perform your marriage. The marriage must be performed no later than 3 months after the stamping of the license.
Some wedding planners include the above services as part of their offered services, so find out if yours does so.