Where natural reefs can't rebuild themselves quickly enough to prevent damage to beaches and fish populations, one environmentally sound solution is to build artificial reefs with Reef Balls -- dome-shaped hollow concrete balls with holes in them that mimic natural coral reefs. Todd Barber, now president of the Reef Ball Development Group Ltd. (RBDG), a volunteer environmental organization, began trying to cover beach balls with chicken wire and concrete. His plan was to float them out to sea, pop the balls, and let the shells sink to the bottom. This is essentially how the perfected Reef Ball works. Concrete offers several advantages in Reef Ball construction. Weight provides stability on the sea floor, while multiple entrances and internal cavities provide shelter. Concrete contains no toxins, and the surface of the balls can be rough and textured to enhance marine growth. Reef Balls carefully designed for the local environment should last hundreds of years. RBDG uses the royalties it receives from its authorized manufacturers to help fund the Reef Ball Foundation, a nonprofit group that supplies free molds and support to other nonprofit and research groups who wish to study or help create Reef Ball reefs. Reef Balls have been deployed off all U.S. coasts, and international use is widespread and growing.