(written from a Production point of view)
Garry Hart is an American television executive, who worked at different levels of Paramount Television.
Born in New York City, Hart obtained a BA in communication studies at Queens College, City University of New York and later an MA and a doctorate from the University of Massachusetts, Amherst.
In 1993, Hart became president of Paramount Network Television. During his tenure, he oversaw the production of Star Trek: Voyager and Star Trek: Enterprise, as well as other successful series like Frasier, NCIS, JAG or Numbers and 71 television movies.
Before the launch of Enterprise, Scott Bakula waited until after he, Kerry McCluggage, and Hart had read the script for "Broken Bow" before accepting the role of Jonathan Archer. Bakula later recalled, "Garry Hart told me when he read the script he immediately thought of me." (Star Trek: The Magazine Volume 2, Issue 9, p. 12)
In 2002, following the departure of Paramount Television Group chairman Kerry McCluggage, the studio was reorganized and Hart became president of television productions. In September 2004, Hart left Paramount to move into independent producing, faced with the planned unification of Paramount and CBS Studios spearheaded by Viacom's co-president Leslie Moonves.
Hart was a strong supporter of Star Trek: Enterprise, reiterating before his departure he hoped for and expected several more seasons. 
Scott Bakula has unequivocally cited Garry Hart as the driving force behind the series' final renewal, thereby thwarting the cancellation intents of UPN, conceivably an instance of "studio politics". (ENT Season 4 Blu-ray special features, "Before Her Time: Decommissioning Enterprise")
In 2014, Hart became professor of radio-TV-film and chair of that department at California State University, Fullerton.