The relationship between the two Koreas shows two distinctively different characteristics during two different time periods: 1) Cold War confrontation during South Korea's military regimes, and 2) greater exchanges and increased dialogue during the civilian governments after the transition to democracy. After South Korea's transition to democracy in 1987, democratization and the end of the Cold War had a significant impact on inter-Korean relations. During the Cold War, tension in the region remained high because of infiltrations and terrorist attacks by the North. South Korea's government's policies focused on national security and considered inter-Korean relations a zero-sum game. In general, both Koreas confronted each other without much dialogue.

The transition to democracy and the end of the Cold War, however, gave way to fundamental change in South Korea's approach to the North. The end of the Cold War allowed South Korea to normalize its relationship with China and the Soviet Union. Because of high levels of public support, South Korea's civilian presidents aggressively pursued engagement with the North and, along with the rest of the world, provided a lot of economic aid and investment for North Korea. As a result, trade between the two Koreas has increased significantly, but these efforts have been largely fruitless in promoting economic reform in North Korea and have failed to halt Democratic People's Republic of Korea (DPRK) efforts to develop nuclear weapons and long-range missiles.