Her diplomatic career started in 2058. (ENT: "Fallen Hero") One of her first responsibilities was negotiating the first territorial accords between Vulcan and Andoria, the Treaty of 2097. (ENT: "Cease Fire")
During a recess of the second Ka'Tann Conference, at Vulcana Regar, she met a young T'Pol, whose presumptuous questions about her negotiating tactics made her reconsider some of her positions. (ENT: "Fallen Hero")
In the 2090s, she negotiated the Territorial Compromise, another treaty between the Andorians and the Vulcans. This treaty laid out rules and regulations regarding Weytahn/Paan Mokar. (ENT: "Cease Fire")
In February, 2152, she had collected enough evidence to testify against them. The Vulcan High Command asked Starfleet to send Enterprise because the nearest Vulcan ship was a week away. They said that it was "imperative she be taken off the planet as soon as possible". Archer and T'Pol were surprised at how friendly she was. V'Lar shook hands with Archer, spoke in English with T'Pol, and met Hoshi to thank her for the use of her quarters. Over dinner at the Captain's table, V'Lar displayed a charm and grace.
The Mazarite criminal element attempted to capture her. They boarded Enterprise and fired their weapons into the chamber they believe was holding V'Lar thinking they had killed her although she was in another part of the ship. The Vulcan ship Sh'Raan arrived and threatened to destroy the Mazarite ships unless they surrender their weapons which they did. V'Lar returned to Vulcan and the criminals on the Mazarite planet were exposed. (ENT: "Fallen Hero")