Specialising in the kids/family genre, Stack has worked as a screenwriter and script reader for companies like Miramax, Working Title, Pathe, UK Film Council and Irish Film Board, among others. He helped set-up the Red Planet Prize with Tony Jordan, designed to seek out new TV writing talent.
With Tim Clague, he co-hosted the highly popular podcast The UK Scriptwriters Podcast, which was started in 2010.