Martyn has been on the TreeHouse School governing body since December 2017 and is now its chair. Martyn is the father of twin boys, one of whom has attended TreeHouse School since 2009. As a parent, he has an understanding of the demands and joys of being a dad to an autistic child and the impact it has on his family's life. After an early background in catering, Martyn then moved into the charity sector, firstly working for one of the City of London livery companies, and then as Finance Director and CEO of St Luke's Trust in Islington. In 2015 he became CEO of United St Saviour's Charity, a large grant-making trust and sheltered housing provider in Southwark. Martyn is also a Ward Beadle in the City of London, a keen cyclist, and cook.