SEALORDS (SL) is a low-to - intermediate complexity, two-player, operational simulation (with important tactical undertones) of riverine combat the Mekong Delta during the Vietnam War. There are two players: the Free World, including US, South Vietnamese and other allies; and the Communists, including Viet Cong and North Vietnamese Army forces. The objective of the Communist player is to infiltrate men and supplies via the Mekong Delta's many waterways, while also attacking critical Free World bases and towns across the region. The Free World player is attempting to prevent that infiltration while also conducting an offensive against Communist formations and bases.

Each player has available several types of riverine and ground units, as well as air units for the Free World player. The Communist player can make use of special rules representing that side's advantage in intelligence and local guerrillas. The system uses an 'operational impulse' system. That is, a player moves and fights with one of his forces, followed by his opponent doing the same with a force of the other side. Every operation requires the expenditure of command points.

SL has several different scenarios, each covering a critical period of operations: Game Warden (the early years), Tet (the Communist general offensive of 1968), and SEALORDS (the Free World counteroffensive of 1969-70). Throughout the course of a scenario, each player accumulates victory Points by eliminating enemy units and taking critical objectives. At the end of the game, the player with the higher total victory point total wins.

Each map grid square equals 6.21 miles (10 km) across, and each full game turn represents a month. Units of maneuver are mostly battalions and battalion equivalents. Playing time for each scenario is about three to four hours. Designed and developed by Joseph Miranda.