Ranju Roy and David Charlton founded Sadhana Mala in 2004. The organization specializes in teacher training, study courses, and retreats. They both studied with TKV Desikachar, Paul Harvey, and Peter Hersnack. They have led training course for Viniyoga and yoga classes and retreats throughout the UK and Ireland. They have personal l contact with more than 2,000 students, several hundred of whom have gone on to become teachers themselves.