[3] On 20 April 2007, South Korean Chief of Naval Operations announced that the lead ship of KDX-III class destroyers will be referred to as Sejong the Great.

[4] The Sejong the Great class is the third phase of the ROKN's Korean Destroyer eXperimental (KDX) program, a substantial shipbuilding program, which is geared toward enhancing ROKN's ability to successfully defend the maritime areas around South Korea from various modes of threats as well as becoming a blue-water navy.

Point-defense armaments include one 30 mm Goalkeeper CIWS and a RIM-116 Rolling Airframe Missile Block 1 21-round launcher, the first Aegis platform to carry RAM.

[12] The Sejong the Great-class destroyers are often compared to the Arleigh Burke and Atago classes because they utilize the AN/SPY-1D multi-function radar, and have similar propulsion and capabilities.

The Sejong the Great class is thus one of the most heavily armed ships in the world,[13] with greater missile capacity than the Chinese People's Liberation Army Navy Type 055 destroyer[14] (112 VLS cells).

While the first three destroyers are fitted with Aegis Baseline 7 based on older proprietary computers that can't carry out IAMD operations, the following three will be fitted with the Baseline 9 version of the Aegis Combat System that combines modern computing architecture to allow the AN/SPY-1D(V) radar to perform air warfare and BMD missions at the same time.

[20] On 10 October 2019, HHI signed a deal to build the first of three 170m long, KDX-III Batch II Aegis destroyers for the ROKN.