Ken Deayton is a CPA qualified in both Australia and Hong Kong, who has been practicing in Hong Kong since 1975. His experience includes four years with the Hong Kong Inland Revenue Department, seven years as head office tax consultant with HSBC and fifteen years as a partner with Deloitte Touche Tohmatsu (Deloitte), where he had overall responsibility for the corporate services division.

Callan hails from the United Kingdom, having grown up in Edinburgh, Scotland, where he was involved in business consulting at the Edinburgh Chamber of Commerce. Callan has also been Chairman of several non-governmental charitable entities, as well as serving a period as General Manager of a United Nations infrastructure company during the Bosnian War 1992-1995.