Diana Richardson is considered to be one of today's leading authorities on human sexuality. She is the best-selling author of eight books on how a person can experience a more fulfilling sex and love life, including O-Books' The Heart of Tantric Sex, which has sold over 71,000 copies to date. Diana has been teaching couples with her partner since 1993, in their informative and life changing Making Love Retreats. They are based in Heimisbach, Switzerland.

Wendy Doeleman is the author of the original Dutch version of Cool Sex (Coole seks, relaxte liefde), first published in 2010. She offers tantra workshops and retreats in the Netherlands, mainly for young people, having worked for many years as a trainer and author in the field of welfare and childcare. Wendy is committed to sex education from a holistic and conscious point of view. She lives in Bilthoven, Netherlands.