Dr David Clarke was appointed Chief Executive Officer at the ETI in 2007. He was employee number one. Over the next ten years he led the organisation with tenacity and vision. Highly respected for his engineering knowledge and ability to communicate the challenges facing the UK energy system, David was well liked and trusted in government and industry circles. At the ETI he was seen as a leader, a colleague and a friend to all. He is missed greatly but the impact of the ETI will be a lasting legacy to the organisation he built, the capability his leadership developed and the people he nurtured who respected and greatly admired him.