Mervyn spent much of his career in the oil industry, with BP, where he held a number of positions in the UK and abroad related to oil trading and the development of refining and petrochemical assets. Since leaving BP, Mervyn has taken an active role in the growth of knowledge exchange and technology spin-outs from universities in Scotland. From the business perspective he has been chairman or a director of a number of companies .
Mervyn was a non-executive member of Court at the University of St Andrews and a council member of the Scottish Funding Council and a member of the advisory board of the marine science research pool (MASTS).
Mervyn is active in the development of corporate governance and he was awarded the Scottish non-executive director of the year in 2009 and the UK director of the year for environmental responsibility in 2010.