Liam was re-elected to the Dail in February 2011 and was previously elected to the Seanad (Cultural and Education Panel) in July 2007. He was appointed Fine Gael's Deputy Leader in the Seanad, and Spokesperson on Finance in October 2007. Liam was first elected to the Dáil in 2002 following a campaign to highlight deficiencies in the health service. He was appointed to Fine Gael Front Bench as Spokesperson on Health in October 2004, where he formulated Fine Gael's innovative health policy for the election in 2007. As Fine Gael's Finance Spokesperson in the Seanad, he was part of the Finance team that met with EU Commissioner Olli Rehn and Ajay Chopra of the IMF.
Liam is married to Dr. Liz O'Sullivan and they have three children. He was raised on the family farm on Clonakilty, Co Cork until he went to study medicine in Trinity College. Liam was instrumental in the setting up of Caredoc, an out-of-hours GP service which covers the entire county of Wexford.