The NIOD Institute for War, Holocaust and Genocide Studies (Dutch: NIOD Instituut voor Oorlogs-, Holocaust- en Genocidestudies) is an organisation in the Netherlands which maintains archives and carries out historical studies into the Second World War. The institute was founded as a merge of the Netherlands Institute for War Documentation (Nederlands instituut voor oorlogsdocumentatie, NIOD, formerly Rijksinstituut voor oorlogsdocumentatie, RIOD) and the Center for Holocaust and Genocide Studies (CHGS).
The institute published Het Koninkrijk der Nederlanden in de Tweede Wereldoorlog (The Kingdom of the Netherlands During World War II) in fourteen volumes and 18,000 pages. The magnum opus of Loe de Jong is the standard reference on the history of the Netherlands during World War II. The NIOD had recently made an electronic edition of the entire work, available for downloading from 11 December 2011, licensed under creative commons CC BY 3.0.