Keith Olsen is an illustrator and writer with a special interest in the outdoors. He has been an outdoor education instructor and advisor. He enjoys tramping and camping and lives with his wife, writer Diana Noonan in Owaka, South Otago.
- Goodbye Toss text by Diana Noonan (HarperCollins 1993).
- The Deer text by Diana Noonan (Ashton Scholastic 1994).
- When the Sun Goes Down illustrated by Geoffrey Notman (Badger Pub 1994).
- A Touch of Jungle Fever text by Diana Noonan (HarperCollins1995).
- Danny to the Rescue text by Diana Noonan (HarperCollins 1995).
- Know, Sow & Grow Kids' Book of Plants written with Diana Noonan (Bridge Hill Pub 1997).
- How to Catch Fish text by Colin Anderson (Bridge Hill Publishing 1999).
- Pick Up a Pack: A Guide to Tramping and Camping the New Zealand Way (Reed 2003).
- Goggle Eyes text by Diana Noonan [Kiwi Bites] (Puffin 2007).