Wilhelmus Simon Petrus "Pim" Fortuyn (pronounced , (February 19, 1948 – May 6, 2002), was a controversial and charismatic politician, author, columnist, public servant and professor in the Netherlands who formed his own party, Pim Fortuyn List (Lijst Pim Fortuyn or LPF). He was assassinated during the 2002 Dutch national election campaign by militant animal rights activist Volkert van der Graaf, who claimed in court he had murdered Fortuyn to stop him from exploiting Muslims as "scapegoats" and targeting "the weak parts of society to score points" in seeking political power.

The official spelling of his family name is "Fortuijn"; later in life he used the spelling "Fortuyn".

Fortuyn was the centre of several controversies for his views about immigrants and Islam. He called Islam "a backward culture" and said that if it were legally possible he would close the borders for Muslim immigrants. He was labelled a far-right populist by his opponents and in the media, but he fiercely rejected this label and explicitly distanced himself from far-right politicians such as the Belgian Filip Dewinter, the Austrian Jörg Haider or Frenchman Jean-Marie Le Pen whenever compared to them. In The Netherlands he is also mainly seen as a populist, more than a fascist or radical right-wing populist While Fortuyn compared his own politics to centre-right politicians such as Silvio Berlusconi of Italy, he also admired former Dutch Prime Minister Joop den Uyl, a socialist. Fortuyn however repeatedly described himself and LPF's ideology as pragmatism and not populism. Fortuyn was openly homosexual.