Delegations from North and South Korea agreed on Friday to arrange the first reunions in three years of some of the families separated by the 1950-53 Korean War.
The reunions - scheduled for August 20 to August 26 - are an emotive issue, especially for the elderly relatives taking part in tearful meetings after decades of separation.
Occasional reunions have previously been arranged during periods of improved relations between the two Koreas.
The Red Cross organisations from the two countries will arrange reunions for about 200 selected people from both sides, they said in a joint statement after a meeting of delegations.
The reunions are among steps promised by Kim Jong-un, the North Korean leader, and Moon Jae-in, president of South Korea, as part of a recent dramatic improvement in relations, after fears of war over North Korean nuclear and missile programmes.
"The whole world is marvelling at the amazing developments between the North and South," said Pak Yong Il, the leader of the North Korean delegation at the talks.
Tensions on the Korean peninsula eased significantly after a summit last week between Kim and Donald Trump, the US president, in which they agreed that they would work towards the denuclearisation of the peninsula.
The reunions will be held at Mount Kumgang, North Korea. South Korean officials have often called for the visits to resume as a "humanitarian and human rights issue", especially since many of the separated family members are now elderly, with many in their 80s and 90s.
The first reunions were held in 1985. About 20 have been held since then with the last in 2015. Since 2000, about 23,676 separated Koreans, from both North and South, have met or interacted through videolink as part of the programme, research said.
But time is running out - 56 percent of the 131,531 South Koreans who initially applied to take part in reunions are thought to have died.