Léon was approached in 2006 by Brussels Airport to set up and organize a new aviation development department after its privatization. Aviation Development at Brussels Airport takes responsibility for airline marketing, B2B and B2C passenger marketing, market analysis, traffic forecasting, market research, and aviation strategy. Brussels Airport has become a regular winner of the Routes Marketing Awards, including winning Routes World in 2012 and 2014. Léon started his career at Fokker Aircraft in 1986 after his study Business Economics at Tilburg University in The Netherlands. Between 1998 and 2006 he worked at Amsterdam Airport Schiphol in the role of Market Research Manager, Marketing Manager and Head of Aviation Marketing.