John Matthews has produced a number of successful divinatory systems based on early spiritual beliefs - including the best-selling Arthurian Tarot (with Caitlin Matthews and Miranda Gray), The Wildwood Tarot (with Mark Ryan and Will Worthington), The Green Man Tree Oracle (with Will Worthington), The Celtic Animal Oracle and Grail Tarot (with Giovanni Casselli). His book, Pirates, was No 1 in the New York Times Book Review and a bestseller for 22 weeks in 2007.

Caitlin Matthews is acknowledged as world authority on Celtic wisdom, the Western Mysteries and cartomancy. She is the author of over 70 books, which have been translated into 19 languages. Her shamanic vocation emerged early in her ability to sing between the worlds and to embody spirits. She specializes in teaching traditional European spirit-consultation oracles in which the diviner draws directly upon the spirits of nature for answers.