Since 2004, Dr. Matthew Clark has been a Research Associate at the School of Oriental and African Studies (SOAS, University of London), where he taught courses on Hinduism between 1999 and 2004. He has spent many years in India, which he first visited in 1977, visiting nearly all important (several hundred) pilgrimage sites and trekking around 2,000 miles in the Himalayas. He first engaged with yoga in the mid-1970s and began regularly practising Ashtanga Yoga in 1990. Since 2006, Matthew has been lecturing worldwide on yoga, philosophy and psychedelics. He is currently the managing editor of the Journal of Yoga Studies and is one of the administrators of the SOAS Centre of Yoga Studies.

His publications include The Daśanāmī-Saṃnyāsīs: The Integration of Ascetic Lineages into an Order (2006), which is a study of a sect of sādhus; The Tawny One: Soma, Haoma and Ayahuasca (2017), which is an exploration of the use of psychedelic plant concoctions in ancient Asia and Greece; and a short book on yoga, The Origins and Practices of Yoga: A Weeny Introduction (revised edition) (2018). In 2021, he published another short book, Botanical Ecstasies: Psychoactive Plant Formulas in India and Beyond.