Born in Glasgow in 1973, Alyn grew up in Scotland and Saudi Arabia, returning to Scotland in 1986. He studied Law and European Law at Leeds University and spent an Erasmus year studying at Heidelberg in Germany. He graduated from Nottingham Law School in 1996. Alyn also gained a Masters degree in European Studies from the College of Europe in Warsaw. After a year teaching English in India and working with Scotland Europa in Brussels, Alyn moved to London where he qualified as a lawyer with commercial law firm Clifford Chance.
In 2000 Alyn moved back to Scotland working first for a legal firm in Edinburgh and from 2002 for Richard Lochhead MSP then the SNP Group at Holyrood as an adviser on European, Justice and Business policies.
Alyn was elected to the European Parliament for the first time in 2004 and has been re-elected twice in the SNP victories in the 2009 and 2014 elections. He is a member of the SNP's National Executive Committee.
Alyn is the Honorary Vice President of the Scottish Society for the Prevention of Cruelty to Animals, Scotland's animal welfare charity. The post is voluntary and unpaid.