Si'tann was a male Vulcan who lived in the late 24th century and was a scientist and Vulcan master.
He was a close friend of Robert Ba'dos, and when was Ba'dos and Kelly Yamashiro were slain in a failed warp funnel experiment in 2353, he took their infant son Jaden as his ward, acting as the boy's patron. He named the child Sovok, and raised him as his own son, instilling in him Vulcan philosophies and teaching him the Vulcan nerve pinch, as he hoped to have a proper Vulcan son. Si'tann encouraged Sovok to enroll first at the Vulcan Science Academy and then at Starfleet Academy.
Later, Ensign Sovok used a holographic program of Si'tann to help him master the Vulcan nerve pinch while on Outpost 40. By 2376, the hologram of Si'tann continued to serve as his patron and Sovok proved himself as a successful pupil by succeeding in the technique. Master Si'tann congratulated Sovok on completing his Vulcan training and honoring the memory of his biological parents.
Following the completion of the Xenophore Seed mission, Sovok consulted the holodeck program of his master once more and wondered on his fate, as he desired to remain assigned to the USS Enterprise. When the ensign received a summons from Captain Jean-Luc Picard, the hologram of Si'tann determined that logic stated that a destiny was forged by the individual's own actions. Thus, he suspected that his pupil's fate had changed and Si'tann was proven correct when Sovok was invited to a card game by Captain Picard (TNG video game: Hidden Evil).