Lewis got his first taste of teaching English in Barcelona in the late 1980s. The experience inspired him to get a Master's in TESOL, after which he taught at a university language centre in Arizona and then a manufacturing company in Japan. In 1995, he took an editorial job with a major publisher in Hong Kong developing materials for Asia, and in 1997 became a freelance editor, project manager and writer in the UK. He has worked on books, videos, tests, audio materials, worksheets, apps and online materials for English learners of all ages across the world. He currently lives in York.