Gruppo N (or Gruppo Enne) was a collective artist group based in Padua, Italy in the early 1960s. Founded by Alberto Biasi and Manfredo Massironi in 1960, the group disbanded in late 1964 before briefly reforming the following year as Gruppo N 65. The group was primarily interested in exploring the optical possibilities to be created in art, and collectively created works that dealt with various perceptive illusions. Artworks were conceived and created collectively, with no sole author per piece. The concepts first explored by the Gruppo N continue to play an important role in Alberto Biasi’s work today.