Beach; Sail Rock Divers; Lotus Dive Resort, both located in Chalok Lam; and Phangang Divers, located in Haad Rin. You will, however, find many more dive schools throughout the island.
Under Thai law, dive operators must be registered with the Tourism Authority of Thailand to improve quality of service, safety and help protect the customer from fraud. Please check to make sure you are booking through a TAT registered dive centre.