The notion of postdramatic theatre was established by German theatre researcher Hans-Thies Lehmann in his book Postdramatic Theatre, summarising a number of tendencies and stylistic traits occurring in avant-garde theatre since the end of the 1960s. The theatre which Lehmann calls postdramatic is not primarily focused on the drama in itself, but evolves a performative aesthetic in which the text of the performance is put in a special relation to the material situation of the performance and the stage.