David studied Interior Design at the Central School of Art and Design in London in the early 1960s when it was possible to do the forerunner to the degree course part time – one full day and three evenings a week. The rest of the week was spent at Heal’s, first at their joinery factory, J. L. Green & Vardy in Islington, and then in Heal’s Design Office in Tottenham Court Road.

The term ‘Interior Design’ was a misnomer. Today, if there were such a course at Central, it would be called ‘Interior Architecture’ and there were several talented architects in the class who wanted to specialise in this area.

After Heal’s and Central, David worked briefly in New York for brand strategy and design company Lippincott & Margulies before returning to London to work for Allied International Designers under the founders, James Pilditch and John Beadle.

David started his own company, David Leon & Partners, in 1973.