Mark O'Brien may refer to:
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Mark O'Brien (actor)
Mark O'Brien (born May 7, 1984) is a Canadian actor and director best known for his roles as Des Courtney in ''Republic of Doyle'' (2010–2014) and Tom Rendon in '' Halt and Catch Fire'' (2015–2016). He won the Canadian Screen Award for Best ...
(born 1984), Canadian actor
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Mark O'Brien (cyclist)
Mark O'Brien (born 16 September 1987 in Horsham) is an Australian cyclist, who last rode for Australian amateur team InForm TM Insight MAKE. He won the 2024 Melbourne to Warrnambool Cycling Classic.
Major results
;2008
: 3rd Road race, Nat ...
(born 1987), Australian cyclist
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Mark O'Brien (footballer, born 1984), Irish footballer, plays for Shelbourne F.C.
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Mark O'Brien (footballer, born 1992)
Mark Leo O'Brien (born 20 November 1992) is an Irish former professional Association football, footballer who played as a Defender (association football), defender. He played in the English Football League for Derby County F.C., Derby County, L ...
, Irish footballer
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Mark O'Brien (poet)
Mark O'Brien (July 31, 1949 – July 4, 1999) was an American journalist, poet, and advocate for the disabled. He has been the subject of two films: ''Breathing Lessons: The Life and Work of Mark O'Brien'', which won an Academy Award in 199 ...
(1949–1999), American poet and advocate for the disabled
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Mark O'Brien (hurler), Irish hurler
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Mark O'Brien (politician), member of the Kentucky House of Representatives
{{hndis, Obrien, Mark