Specially designed landing ships were first employed by the British in Operation Torch, the invasion of North Africa in 1942. The British recognized the need for such ships after the debacle at Dunkirk in 1940, when they left behind tons of badly needed equipment because no vessels were available with the capability to bridge the gap between the sea and the land. Following the evacuation, Prime Minister Winston Churchill (Churchill, Sir Winston) sent his minister of supply a memorandum posing the question,

As an interim measure, three shallow-draft tankers were converted to LSTs. The bows were redesigned so that a door, hinged at the bottom, and a 68-foot- (21-metre-) long double ramp could be fitted to the vessels. These modifications made it possible for vehicles to disembark directly from the ship to the beach. Both the new design and the vessel were considered unsatisfactory, but the concept was sound.

At the request of the British, the Americans (United States) undertook the redesign and production of LSTs in November 1941, and John Niedermair of the Bureau of Ships designed a ship with a large ballast system. Deep-draft ships were necessary to cross the ocean, and shallow-draft vessels were required to bridge the water gap. A newly proposed ballast system gave one ship both capabilities: when at sea the LST took on water for stability, and during landing operations the water was pumped out to produce a shallow-draft vessel. The American-built LST Mk2, or LST(2), was 328 feet in length and 50 feet wide. It could carry 2,100 tons. Built into the bow were two doors that opened outward to a width of 14 feet. Most Allied vehicles could be transported on and off-loaded from LST(2)s. The lower deck was the tank deck, where 20 Sherman tanks could be loaded. Lighter vehicles were carried on the upper deck. An elevator was used to load and off-load vehicles, artillery, and other equipment from the upper deck; in later models a ramp replaced the elevator. The vessel was powered by two diesel engines, and it had a maximum speed of 11.5 knots and a cruising speed of 8.75 knots. LSTs were lightly armed with a variety of weapons. A typical American LST was armed with seven 40-mm and twelve 20-mm antiaircraft guns.

Numerous other types of landing ships were produced by the British and Americans during the war. Examples are the Landing Ship, Infantry (Large), or LSI(L), named Auxiliary Personnel Attack Ship (APA) by the U.S. Navy; the Landing Ship, Headquarters, or LSH, named Command Ship by the U.S. Navy; the Landing Ship, Dock, or LSD; and the Landing Ship, Medium, or LSM. Some vessels called “landing ships” did not have the capability to off-load troops and supplies onto beaches; they were in fact simply transports or command-and-control vessels.

During the Korean War, LSTs were employed in the Inch'ŏn landing. Limited numbers of LSTs were produced in the 1950s and '60s. The most prominent were the diesel-powered Newport LSTs, which were built for the U.S. Navy in the 1960s. These vessels displaced more than 8,000 tons fully loaded and transported amphibious craft, tanks, and other combat vehicles, along with 400 men, at speeds of up to 20 knots. Such speeds were made possible by abandoning the bow doors of their World War II predecessors in favour of an extendable ramp supported by huge projecting derrick extensions on each side of the bow. As the ship beached, the ramp would shoot forward hydraulically 112 feet. Vehicles and troops would land over the ramp, while amphibious craft in the tank deck would disembark from stern gates.