Leon started as an apprentice in a London Mayfair art studio followed by two years in the creative/art departments of two London advertising agencies. He then set up on his own as a freelance living and working in London.

He has produced thousands of single joke cartoons and comic strips for newspapers, magazines, greetings cards, calendars, advertising and character merchandising over many years, drawing under his nom-de-plume "Leon".  He created and drew the syndicated cartoon strip Aphrodite, the pocket cartoon Sporting Fanny for the Sunday People and a wide range of advertising cartoons, character merchandising art.  He also drew cartoons for OUI Magazine of Playboy Publications Inc.