Alastair served an electrical apprenticeship and joined the Merchant Navy.
He became an electrical inspector in the power industry, was a trade union representative and a member of the local Royal Society for the Prevention of Accidents.
Alastair started an electrical company in 1979.
Alastair was elected an SNP councillor in East Renfrewshire in 2007. He was elected Provost of the Council in 2012.