Before entering politics he worked in RTÉ as a Programme Executive. Andrews was first elected to Dáil Éireann at the 1977 general election for the Dublin County South constituency and later for the Dublin South constituency. He held his seat at each subsequent election until he decided not to contest the 1987 general election. He had been elected to the European Parliament in 1984 for the Dublin constituency and decided to concentrate on European politics instead of domestic. He remained an MEP until his retirement in 2004. He was Minister of State at the Department of the Environment in 1982.