Seamús McDonald has been a member of Laois County Council since 1985 and Chairperson in 1996-1997. He is a member of the Executive of the General Council of County Councils and the Local Authority Members Association. Seamús is a member of the Barrow Drainage Board as well as Chair of the Housing Strategic Policy Committee. He is also Chair of both Rosenalis FAS and Rosenalis Community Centre Committee.
In May 2014 he was re-elected to Laois County Council.