A wave-attenuating system. The wave-attenuating system includes a flexible, resilient barrier member that is disposed in a body of water and oriented to interrupt and dissipate the wave action of oncoming waves. The barrier member desirably is constructed from a substantially neutrally or slightly negatively buoyant material so that the overall depth, length, and/or thickness can be increased as needed for a particular application while adding little deadweight to the system in water. The barrier member can be supported by a flotation device in a floating breakwater, or alternatively, the barrier member can be secured to a stationary structure in a fixed breakwater.