Vishnujana Swami (IAST: Viṣṇujana Svāmī; San Jose, June 2, 1948 - Mayapur, March 16, 1976), born Mark Stephen D'Atillo, was a disciple of A. C. Bhaktivedanta Swami Prabhupada, and a sannyasi within the International Society for Krishna Consciousness (commonly known as the 'Hare Krishnas' or ISKCON). Despite his mysterious disappearance in 1976, he continues to be regarded as a saintly figure within ISKCON. His legend lives on through recordings of his celebrated singing of the Hare Krishna mantra and through his unmatched success as a preacher in the early days of the movement.