(written from a Production point of view)
James D. "Jim" Ballas, ACE (24 April 1915 – 8 December 1979; age 64) was a film editor who worked on the first two seasons of Star Trek: The Original Series. Ballas started his career as a sound effects man and quickly moved up to film editor. From the early 1950s onward, he edited one feature film, The Shaggy Dog (1958, with Gregg Palmer) and a dozen television series. These included The Broken Arrow, Green Acres, The Fugitive, and Night Gallery.
Ballas left Star Trek in late 1967 while cutting "The Omega Glory". At the annual Paramount/Desilu Christmas party, Ballas (after a few drinks) told William Shatner how his "telegraphed reactions" made his job of editing much more difficult. After some heavy arguments, they had to be separated by fellow party-goers. Ballas did not return for the third season. (Inside Star Trek: The Real Story, pp 370-371)