Harry is the most junior of the senior officers, and hates feeling like the baby.  He has survived many new experiences in his first, and possibly last, duty station.  He has been killed twice, once during his transference into the next emanation and once by being sucked out of the ship during a hull breach.  The Harry on Voyager now is actually a "twin" of another Harry from another Voyager in an alternate timeline (Deadlock).

Tom Paris is Harry's best friend, since the moment they met in Quark's bar on Deep Space Nine.  He risked his life in a special effort to save Tom while they were both falsely convicted and imprisoned.  Harry also has a good relationship with B'Elanna Torres, and he occasionally calls her "Maquis" while she calls him "Starfleet".

In his spare time he likes to play his clarinet. He is a wonderful player and once played in the Juliard Youth Symphony.  Harry enjoys holonovels, including Beowolf.  He also plays pool at Sandrine's poolhall in the holodeck.

Harry is an only child and was very close to his parents, always calling them at least once a week. He also had a girlfriend in the Alpha Quadrant, named Libby, that he was loyal to, but since being in the Delta Quadrant he has been involved with a few women.