Harry van der Zee specialised in classical homeopathy at the SHO (Foundation for Homeopathic Education for Doctors) in the Netherlands from 1987 to 1990.
He has been practising homeopathy in Haren since 1987. For many years he has been teaching homeopathy around the world, the emphasis of his teaching being on recognising themes and patterns in a patient's history, as well as on a deeper understanding of the themes and patterns in remedies.
Since 1996 he is editor of Homeopathic Links, and in 2002 founded together with Corrie Hiwat the publishing house Homeolinks Publishers.
Since 2004 he is actively involved with Peter Chappell and his projects for treating AIDS and other epidemics, for which in 2007 he co-founded the Amma Resonance Healing Foundation.
In 2008 he published the Amma4Africa Manual - Basic Guide to Treat Infectious Diseases and Trauma, and in 2012 together with Peter Chappell Homeopathy for Diseases - Vital Remedies for Epidemics, Trauma & Chronic Diseases.
With Christopher Johannes he co-authored Homeopathy & Mental Health Care - Integrative Practice, Principles and Research (2010).