Coral reefs are among the world's most diverse and complex ecosystems. A habitat for thousands of plant and animal species, for centuries reefs have also offered food, sheltered coastlines from storms, and been a source of important medicinal products. Coral reefs are vast, untapped pharmaceutical resources; from a medical perspective, the potential importance of reefs is yet to be fully realized. With the highest density of animals anywhere on the planet, coral reefs surpass even tropical rainforests in future medicinal possibilities, even without considering the potential of the coral itself. And yet, humans threaten the very existence of coral reefs. Like rainforests, if coral reefs are not cared for, if conservation measures are not implemented, these magnificent ecosystems will be lost to the world.