Smith was still on the bridge when the Enterprise entered the galactic barrier. Just prior to the ship's impact with the barrier, Smith held helmsman Gary Mitchell's hand for support. When Mitchell received a shock from the barrier, she was still holding his hand and she did not receive the shock – Mitchell, though, had high ESP potential. (TOS: "Where No Man Has Gone Before")
In the script of "Where No Man Has Gone Before", Yeoman Smith is described as "female, pert, early twenties."
The gag that involves Kirk mistaking this character's name as "Jones" was scripted to appear not only once, as in the episode's final version, but also be repeated at the end of the installment (shortly before Kirk makes his final log entry of the episode). In the final edit, Smith does appear in that scene, but only briefly.
Yeoman Smith was played by actress and model Andrea Dromm. Herbert F. Solow once recalled that Gene Roddenberry finding Dromm attractive was the reason she was cast in the part; "Actually, it was a non-part. But during the casting process, director Jimmy Goldstone overheard Gene say, 'I'm hiring her because I want to score with her.' It was not only a non-part, I'm pretty sure it was a non-score as well." (Inside Star Trek: The Real Story, p. 79)