Statistics for Tandem Breakwater consists of a submerged reef breakwater constructed at some distance in front of a conventional non-overtopping rubble mound breakwater. The submerged reef breakwater breaks the high waves and the stilling basin between two breakwaters attenuates them. Hence, smaller waves approach the non-overtopping rubble mound breakwater and break on it. Therefore, the non-overtopping rubble mound breakwater may be designed for smaller waves, resulting in relatively lighter armour stones. In the model studies, it has been found that for a relative breakwater spacing X/d varying from 3.33 to 4.29 between the breakwaters, the damage of a tandem Breakwater is 20% to 60% less as compared with a single breakwater for similar operating criteria. © 2003 Taylor & Francis Group, LLC.