Having completed a course in fashion design at Salisbury College of Art, Dillon moved to London and was employed by milliner Mitzi Lorenz, working in the model workroom gaining experience and getting groundwork to build on.

He then took a position at Philip Somerville, working in the Bond Street atelier furthering his knowledge in traditional millinery couture techniques. Began designing pieces for both the couture and ready to wear ranges, and after being appointed design director, the whole collection was soon amongst designers designing for Diana, Princess of Wales, her majesty Queen Elizabeth II, and other socialites and celebrities.  Philip Somerville was appointed the royal warrant, milliner to her majesty the queen in 1995.

In summer 2009 Kate Middleton was spotted wearing one of Dillon’s designs at the order of the garter ceremony at Windsor castle.

Other projects have been for stage and screen, designing Joan Collins' hats for a production of Noel Coward's 'private lives', the hats in James Bond - 'Goldeneye', various advertising campaigns and working with fashion designers, producing hats for catwalk shows.

In spring 2009 Dillon started his own business - designing under his own name, Dillon Wallwork bespoke hats.  Continuing to work in the same ethos as Philip Somerville and using his 25 years experience to produce beautiful millinery using traditional techniques in a modern way.
In summer 2009 Dillon was tutor at millinery workshops held at chateau dumas, south west France - some of which coincided with the hat festival at Septfonds, more workshops are planned for 2010.