South African Institute for Maritime Research (SAIMR or SAIMAR, pronounced ) is the name of a shadowy paramilitary organization that supposedly performed clandestine operations to support white supremacy in Africa. The SAIMR first became publicly known during sessions of the South African Truth and Reconcilliation Committee (TRC), in 1998, a year before the second elections after Apartheid, when documents emerged implying SAIMR had a role in a plot to kill Dag Hammarskjöld, the UN Secretary-General, in 1961.

Letters with SAIMR’s official letterhead were found during the hearings of South Africa’s Truth and Reconciliation Commission in 1998. The letters suggested that MI6 and the CIA had agreed that Hammarskjöld should be removed, a suggestion both organizations denied.

The documentary Cold Case Hammarskjöld, that premiered in January 2019, brought renewed media attention to these claims. The documentary also claims that the mother of a young woman named Dagmar Feil tried to bring the killing of her daughter to the attention of the TRC, implying that her daughter had worked with SAIMR to spread HIV among black people and had wanted to make that public.