Alynna Nechayev served as Vice Admiral for Starfleet until 2369, when she was promoted to Admiral. In 2370 she received the rank of Fleet Admiral and Commander Wrightwell was her aide. Nechayev had a particular fondness for Bularian canapés, though she thought them fattening. Nechayev spent much of the 2360s and early 2370s dealing with issues near the Cardassian border.
Nechayev was a significant figure in Starfleet's dealings with the Cardassian Union and a fierce advocate of Federation security. She was Captain Jean-Luc Picard's direct superior but had a poor working relationship with him. In 2369, she ordered Picard to relinquish command of the Enterprise to Captain Edward Jellico, the latter having experience with Cardassians in the past and having worked to establish the original armistice of the Federation-Cardassian War. She assigned Picard to a special operation to infiltrate a Cardassian installation on Celtris III. After Jellico's negotiations with Gul Lemec worsened, she authorized his actions against the Cardassian warships in the McAllister C-5 Nebula, at the risk of provoking open war. (TNG: "Chain of Command, Part I", "Chain of Command, Part II")
Nechayev believed that Picard was too soft-handed in his dealings with Federation adversaries. She cited in particular his refusal to use Hugh as a carrier to introduce an invasive program into the Borg Collective. When she later commanded the Starfleet task forces assembled in response to the Borg attack of 2369, she ordered Picard to deploy the program should another opportunity avail itself. Picard tried making amends in 2370, offering her Bularian canapés to help her feel welcome on board the Enterprise. However, his objections to her order removing the Native American colonists from the Dorvan V colony in the Demilitarized Zone left tension between the two. (TNG: "Descent", "Journey's End")
Nechayev also played a role in the Federation-Cardassian Treaty of 2370, and subsequently oversaw Starfleet's response to the Maquis insurrection. Though she understood the Maquis position, she was committed to preserving the Federation's peace with the Cardassians. As part of her efforts, she requested Ro Laren's participation in an undercover mission to infiltrate the Maquis. (DS9: "The Maquis, Part II"; TNG: "Preemptive Strike")
Nechayev was used in a simulation performed by the Vorta Borath to investigate possible reactions of Benjamin Sisko, Jadzia Dax, Miles O'Brien, Julian Bashir and Subcommander T'Rul to an increased Dominion presence in the Alpha Quadrant in 2371. In this simulation, Nechayev informed Sisko that Deep Space 9 was being handed over to the Dominion, an agreement the Bajorans strongly objected to. (DS9: "The Search, Part II")
Later that year, when the crew of Deep Space 9 had recovered a Jem'Hadar youth, and Odo opted to return him to the Dominion rather than to hand them over to the incoming USS Constellation, Sisko justified the change of plans by stating that while Admiral Nechayev won't like it, "I would've had to kill the boy to keep him here." (DS9: "The Abandoned")
Nechayev was shown with the insignia of a vice-admiral in each of her appearances.
Nechayev has also appeared in numerous novels including the Star Trek: New Frontier series, the A Time to... series, and the Star Trek: Destiny trilogy, as well as in Rogue Saucer, Hollow Men and Before Dishonor. She also appears in the Shatner/Reeves-Stevens books as Starfleet commander-in-chief, and commands the USS Sovereign. Nechayev is also available as a commanding officer in the Federation campaign of Star Trek: Deep Space Nine - Dominion Wars. She also appears as a Starfleet Intelligence agent in the Star Trek: Terok Nor novel, Day of the Vipers.