Although ultimately unsuccessful, the Korvat Negotiations of 2289 established a period of detente between the Federation and the Klingon Empire. It was hoped that the discussions would once and for all end the cold war between the two powers. Unfortunately, neither side could completely agree on the amount of demilitarization along their borders. (Deep Space Nine: "Blood Oath")
The legendary Curzon Dax represented the Federation, while the Empire was represented by Kang and Koloth.