Trained as a journalist, Tessa Duder began writing fiction when she was thirty-eight and has published six children's novels including the Alex quartet. The paperback of Alex is one of Penguin New Zealand's best-selling children's books (over 25,000 copies sold), and in 1993 Isambard adapted the book to make a feature film. Her Alex novels have won three New Zealand Children's Book of the year awards and three Esther Glen medals, and are published in America, Britain, Australia, Canada and in five languages. Jellybean and Alex has also been named American Library Association Honour Books. In recent years Tessa has taught creative writing at the University of Auckland's Centre of Continuing Education, at summer schools in Auckland and Hamilton, and frequent one-day seminars for both adults and children around the country. She is currently a tutor for the Access Literacy Trust's adult literacy programme.
Between 1992 and 1996, she was a member of the drama quartet Metaphor which presented over 80 performances. Tessa has taken voice lessons from Linda Cartwright and acting lessons from Raymond Hawthorne and appeared, in a guest role for five weeks, on Shortland Street. Among her leisure interests are theatre-going, music, reading and sailing.