William Carey started his career serving in The Blues and Royals. Having completed a short service commission, he then worked for a number of well known investment management companies before co-founding Liontrust Asset Management PLC in 1995, a business successfully listed on the London Stock Exchange in 1999. William continued as Joint Chief Executive until stepping down in 2004. During his time, the business grew to approximately £5 billion of funds under management with a market capitalisation of approximately £150 million. Since 2005, he has been involved in diverse projects ranging from investing in a small hotel business in Morocco to a political website called Hustings.com, that aims to get more people to engage in politics.

William became a Member of the Chartered Institute of Arbitrators as an Accredited Mediator in May 2006. In 2008, he was involved in setting up a rally team that enabled two young crew members to compete at a high level where they enjoyed considerable success. His main focus is now photography.