Meaney's first television appearance was in Z-Cars on BBC 1, in 1978.
He guest-starred on shows such as Remington Steele and Moonlighting before embarking on a successful film career; he received a Golden Globe nomination for Best Actor for his role in The Snapper.

Meaney first appeared on Star Trek: The Next Generation in its 1987 pilot episode, "Encounter at Farpoint", as an unnamed helm officer.
His character became a frequently recurring one, and was given the name of Miles O'Brien as he became more prominent in the crew as Transporter Chief.
In 1993, Meaney left The Next Generation for a main role in its spin-off Star Trek: Deep Space Nine and remained on that show until its final episode, in 1999.
With 225 total appearances on Star Trek, he has made more appearances on the franchise than any other actor except Michael Dorn.

Meaney played Colum O'Hara in the 1994 miniseries Scarlett, the sequel to Gone With the Wind.
He has played a minor recurring role as Cowen, leader of the Genii on the Sci-Fi Channel (now Syfy) series Stargate Atlantis, guest-starred on Law & Order, Law & Order: Criminal Intent and appeared as Bob O'Donnell on the ABC show Men in Trees.

He was the only actor to appear in all three film adaptations of Roddy Doyle's The Barrytown Trilogy, wherein he played the father of the Rabbitte family.
Due to rights issues, the family name was changed from film to film.
His stage appearances include the Old Vic production of Eugene O'Neill's A Moon for the Misbegotten.
Meaney starred in British comedy film Three and Out released in the UK on 25 April 2008.
In July of the same year An Post (the Irish Post Office) issued a postage stamp showing Meaney as Joe Mullen in the film Kings.

In 2009, Meaney co-starred with Gerard Butler and Jamie Foxx in Law Abiding Citizen, wherein Meaney played Detective Dunnigan.
In March 2009, Meaney guest-starred as an Irish bartender on the St. Patrick's Day episode of The Simpsons, "In the Name of the Grandfather".
In the same month the film The Damned United was released, a mostly fictional retelling of the 44-day period in which Brian Clough was manager of Leeds United.
Meaney played the former Leeds manager Don Revie.
He also co-starred in Soldiers of Fortune with Christian Slater and Ving Rhames.
 In 2013, Meaney co-starred with Steve Coogan in Alan Partridge: Alpha Papa.
In 2014, he appeared as The Horse in the BBC's three-part crime story, The Driver.
For five seasons he portrayed railroad magnate Thomas Durant on AMC's drama series Hell on Wheels.
Meaney's first television appearance was in Z-Cars on BBC 1, in 1978. He guest-starred on shows such as Remington Steele and Moonlighting before embarking on a successful film career; he received a Golden Globe nomination for Best Actor for his role in The Snapper.
Meaney first appeared on Star Trek: The Next Generation in its 1987 pilot episode, "Encounter at Farpoint", as an unnamed helm officer. His character became a frequently recurring one, and was given the name of Miles O'Brien as he became more prominent in the crew as Transporter Chief. In 1993, Meaney left The Next Generation for a main role in its spin-off Star Trek: Deep Space Nine and remained on that show until its final episode, in 1999. With 225 total appearances on Star Trek, he has made more appearances on the franchise than any other actor except Michael Dorn.
Meaney played Colum O'Hara in the 1994 miniseries Scarlett, the sequel to Gone With the Wind. He has played a minor recurring role as Cowen, leader of the Genii on the Sci-Fi Channel (now Syfy) series Stargate Atlantis, guest-starred on Law & Order, Law & Order: Criminal Intent and appeared as Bob O'Donnell on the ABC show Men in Trees.
He was the only actor to appear in all three film adaptations of Roddy Doyle's The Barrytown Trilogy, wherein he played the father of the Rabbitte family. Due to rights issues, the family name was changed from film to film. His stage appearances include the Old Vic production of Eugene O'Neill's A Moon for the Misbegotten. Meaney starred in British comedy film Three and Out released in the UK on 25 April 2008. In July of the same year An Post (the Irish Post Office) issued a postage stamp showing Meaney as Joe Mullen in the film Kings.
In 2009, Meaney co-starred with Gerard Butler and Jamie Foxx in Law Abiding Citizen, wherein Meaney played Detective Dunnigan. In March 2009, Meaney guest-starred as an Irish bartender on the St. Patrick's Day episode of The Simpsons, "In the Name of the Grandfather". In the same month the film The Damned United was released, a mostly fictional retelling of the 44-day period in which Brian Clough was manager of Leeds United. Meaney played the former Leeds manager Don Revie. He also co-starred in Soldiers of Fortune with Christian Slater and Ving Rhames.  In 2013, Meaney co-starred with Steve Coogan in Alan Partridge: Alpha Papa. In 2014, he appeared as The Horse in the BBC's three-part crime story, The Driver. For five seasons he portrayed railroad magnate Thomas Durant on AMC's drama series Hell on Wheels.
Colm Meaney