Over this time he has done everything from designing, producing, marketing, PR and script writing to managing and running companies. He has worked freelance for a range of companies including Sega, Electronic Arts, Hasbro, Activision, Microprose and SCI. He has worked as Creative Director at Quicksilva ('Golden Age' games and hardware), Head of Design at Hollis Research (massively multiplayer Internet games) and Partner at Focus Creative Enterprises (design and graphics) and as Head of Design at Rebellion Developments.

As one of the early pioneers of the videogames industry Mark was the first person to write blurb for games in an effort to create large fictional worlds for people to play in, the first person to licence characters for games (in the UK) and worked on a range of ground breaking titles.

In those early days there was no games industry, Mark and his colleagues had to invent it as they went along. There were probably no more than fifty people (in the UK) working in the whole industry when he started out!

Mark has designed across three generations of consoles and handhelds and twenty years of computers.

Recently he has been at the forefront of research and development of Internet and mobile phone games.

He is currently Head of Design at Rebellion.