[1] Born in Hawick on 11 December 1949, in the Borders Region, he was recruited by the SNP, after failing to win the Scottish Conservative nomination, to contest the Hawick and Denholm ward for the party in the 2012 Scottish Borders Council election.
[2] He polled 381 first preferences, and after transfers, secured the last seat in the ward on the sixth count at the expense of the Scottish Liberal Democrats.
After the election the SNP formed a coalition administration with the Lib Dems and with Independents.
Alastair had been intrigued by a conference presentation on the subject and subsequently travelled to Germany where there were 260 machinery rings in operation at the time.
Since then Cranston was involved in the development of rural recycling and renewable energy initiatives related to linking communities and agriculture.