'AB Aktion' was a German undertaking to eliminate Poland’s ability to effect any revival as opposition to the establishment of a German 'new order' in eastern Europe (September 1939/June 1940).

The 'AB Aktion', or in full the Ausserordentliche Befriedungsaktion (extraordinary pacification action) was an attempt to locate, seize and kill Polish intellectuals and both actual and potential leaders who might otherwise be able to organise resistance to the German occupation. It is believed that some 30,000 Poles were seized, some 7,000 political and religious leaders, professors, and teachers being killed and the other 23,000 sent to concentration camps.

From a time late in 1939 into early 1940, most university professors and lecturers, intellectuals, writers, politicians, teachers and other members of the Polish intelligentsia were subjected to preliminary arrest by the Gestapo and had their names registered.

As governor-general of the Generalgouvernement from 26 October 1939, Hans Frank approved the 'AB Aktion' on 16 May of the following year, and during the weeks which followed the German police, Gestapo, Sicherheitsdienst and military units seized some 30,000 Poles in major cities such as Warsaw, Łódź, Lublin and Kraków. These Poles were interned in a number of prisons and subjected to interrogation by Nazi officials. The seized Poles were then moved from the prisons of Warsaw, Kraków, Radom, Kielce, Nowy Sącz, Tarnów, Lublin and other places to concentration camps, most especially that newly created at Auschwitz, as well as Sachsenhausen and Mauthausen.

As noted above, about 7,000 members of the Polish intelligentsia were killed in mass executions in Palmiry near Warsaw, Firlej, Wincentynów near Radom, and in the Bliżyn forest near Skarżysko-Kamienna.