An undersecretary was a high-ranking civilian title held by Federation officials.

Nilz Baris was undersecretary in charge of agricultural affairs in the quadrant where Sherman's Planet was located. As undersecretary, he was responsible for the colonization project on Sherman's Planet. The title also gave him the authority to issue a Code One alert. (TOS: "The Trouble with Tribbles")

It is likely the undersecretary for agriculture is somehow linked to the Federation Cabinet.