Prof. Dr. Habil. Krzysztof Leśniewski (1960) is a Polish theologian. Since 1996, an employee of the Faculty of Theology in the John Paul II Catholic University of Lublin, and since 2008 the head of the Chair of Orthodox Theology at the same university. He is a member of the European Society for Ecumenical Research „Societas Oecumenica", the International Ecumenical Fellowship, Societas Scientiarum Internationalis „Fides et Ratio”. The main areas of his research: theological anthropology, spirituality of the Christian East, hesychastic diagnosis and therapy, and thanatology. He is author of four books (translated also into French, Spanish, and Lithuanian) and more than one hundred articles and chapters on Orthodox theology and spirituality.