Abstract: A modular enclosure system particularly suited for use aboard a ship comprises a modular enclosure which is easily installed into and removed from an exoskeletal frame that is shock-mounted to a fixed surface, such as the deck of a ship. An enclosure is installed by placing it within a respective frame via complementary guide rails. A securing mechanism locks the enclosure into place within the frame, and an ejection mechanism enables an enclosure to be easily removed for purposes of maintenance, repair or reconfiguration, or in the event of an emergency. The enclosures are preferably water-tight and float if ejected into the sea. Rubberized boots surrounding all points of entry enhance the survivability of the enclosures in a nuclear/biological/chemical (NBC) environment. Shock-mounting the frames to the deck eliminates the need to shock-mount individual pieces of equipment and enables the use of cheaper and more readily available commercial off-the-shelf equipment.