Herman Zimmerman, or H. Zimmerman, was a Starfleet officer from the late 23rd to late 24th century.
In 2293, Captain Zimmerman was assigned to the Office of Science Ops, according to the dedication plaque of the USS Enterprise-B. (Star Trek Generations, dedication plaque)
He was named as a design engineer on the dedication plaque of the USS Stargazer, which was launched in 2326. (TNG: "The Battle")
In 2364, he was the commander of the USS Nightwing. (TNG: "Conspiracy", okudagram)
In 2368, he was listed as being part of the Engineering Group on the second dedication plaque of the USS Enterprise-D. (TNG: "Silicon Avatar", dedication plaque)
In 2370, he was the commander of the USS Yorktown on a Deep Space 9 arrival roster. (DS9: "Whispers", okudagram)
He was listed as being the part of the Science Ops team on the dedication plaques of Defiant-class starships USS Defiant (2370), USS Valiant (2372), and USS Sao Paulo (2375). (DS9: "The Die is Cast", dedication plaque; DS9: "Valiant", USS Valiant dedication plaque; DS9: "The Dogs of War", dedication plaque)
In 2372, he was listed as belong to the Spaceframe Development team on the dedication plaque of the USS Enterprise-E. (Star Trek: First Contact, dedication plaque)
In 2401, he was listed as a member of the Admiralty Board on the dedication plaques of the USS Stargazer, USS Titan-A, and USS Enterprise-G. (PIC: "The Star Gazer", "The Next Generation", "The Last Generation")