She began her broadcasting career as a researcher on ITV’s 'This is Your Life', when she moved to London in the mid 1980s.
She joined the BBC as a producer in 1987 and went on to become a reporter on the BBC programme 'Newsnight'. She later returned to Dublin and has been presenting the current affairs programme 'Prime Time' since 1996.
In 2000, she co-founded independent production company Mint Productions. She won an IFTA for Best TV Personality in 2003. She began presenting a summer chat show, 'Saturday Night With Miriam', in 2005 and also presents a radio show, 'Miriam Meets.'