This collection of essays honours the memory of the late Pandit N.R. Bhatt, who contributed to pioneering research into the history of _aivism in the French institutions of research in Pondicherry, notably through his editions of Sanskrit works of the _aivasiddh_nta and through his work of gathering the largest collection of _aiva manuscripts worldwide, recognised as a Memory of the World collection by UNESCO in 2005. After a preface about N.R. Bhatt?s life and a bibliography of his ?uvre, sixteen contributions by colleagues and disciples cover aspects of the history of tantrism, of _aiva ritual and doctrine. Two more articles deal with iconography and one last contribution publishes an eighteenth-century account of the siege of Pondicherry in 1778.