Film and television producer/director, Hal McElroy left school at age 16 and initially began working in advertising. He later accepted a position as assistant/gofer with director Fred Schepisi. In 1971 he and his twin brother James set up the film production company Salt Pan Films (later McElroy and McElroy), after a number of frustrating experiences with various film companies. Their debut film was the 1974 feature The Cars that Ate Paris, directed by Peter Weir. It became the first Australian film to gain international recognition at the Cannes Film Festival. The McElroy brothers' next two films were also directed by Weir, these being the critically-acclaimed Picnic at Hanging Rock (1975) and The Last Wave (1977).
Hal McElroy's credits as a producer include a range of feature films, television programs and telemovies, including: Blue Fin (1978), Ratbags (1981, TV), Return to Eden (1983, TV miniseries) , Razorback (1984), Return to Eden (1986, TV series), A Dangerous Life (1988), Blue Heelers (1994-2006), The Sum of Us (1994), Water Rats (1996-1999), Dog's Head Bay (1999), Balmain Boys (2002) and Sea Patrol (2008).
McElroy is also credited with writing episodes for Murder Call (2000), Water Rats, Blue Heelers and Sea Patrol. His credits as an assistant director include: Flashpoint (1972), Alvin Purple (1973), The Man from Hong Kong (1975), The Great McCarthy (1975) and Caddie (1976).
The McElroy brothers dissolved McElroy and McElroy in March 1992, with Hal focusing his attention on television production (James McElroy turned primarily to feature film production). Soon afterwards, Hal established Southern Star McElroy, an independent subsidiary division of Southern Star Entertainment. McElroy left Southern Star in 1997 and founded McElroy Television in April the following year. In 1999 McElroy's parent company Eden Productions Pty Ltd sued Southern Star Entertainment for AUS$10.5 million over alleged non-payment of royalties from Blue Heelers and Water Rats. Southern Star subsequently mounted its own lawsuit against McElroy's company for $140,000 it claimed was owed by Eden.
McElroy Television was rebranded McElroy All Media in early 2005, with its operations overseen by Chief Executive Officer Di McElroy.