Most of the guest-facing personnel on the island are the crew members aboard the ship - servers, bartenders, and activities directors are a few of the familiar faces on the island. There's around 140 cast members who live on the island year-round and work in facility maintenance, engineering services, horticulture, custodial, transportation, etc. Then they'll boat in additional employees from adjacent Bahamian islands who run excursions, work at some of the stores, hair braiding, etc.
Castaway Cay (formerly known as "Gorda Cay") was purchased by Disney in 1997 from the Bahamian Government in a 99-year land lease.
The island is 1,000 acres and still largely undeveloped, as only 55 acres have been developed for the cruise line private island.

