In Buenos Aires (1946) he founded the Altamira academy together with some of his students, and made public the White Manifesto, which states: "Matter, colour and sound in motion are the phenomena whose simultaneous development makes up the new art".

[8] Following his return to Italy in 1948 Fontana exhibited his first Ambiente spaziale a luce nera ('Spatial environment') (1949) at the Galleria del Naviglio in Milan, a temporary installation consisting of a giant amoeba-like shape suspended in the void in a darkened room and lit by neon light.

[9] Fontana often lined the reverse of his canvases with black gauze so that the darkness would shimmer behind the open cuts and create a mysterious sense of illusion and depth.

With his Pietre (stones) series, begun in 1952, Fontana fused the sculptural with painting by encrusting the surfaces of his canvases with heavy impasto and colored glass.

[14] In 1959 Fontana exhibited cut-off paintings with multiple combinable elements (he named the sets quanta), and began Nature, a series of sculptures made by cutting a gash across a sphere of terracotta clay, which he subsequently cast in bronze.

[15] Fontana engaged in many collaborative projects with important architects of the day, particularly Luciano Baldessari, who shared and supported his research for Spatial Light – Structure in Neon (1951) at the 9th Triennale and, among other things, commissioned him to design the ceiling of the cinema in the Sidercomit Pavilion at the 21st Milan Fair in 1953.

[16] Around 1960, Fontana began to reinvent the cuts and punctures that had characterized his highly personal style up to that point, covering canvases with layers of thick oil paint applied by hand and brush and using a scalpel or utility knife to create great fissures in their surface.

In 1961, following an invitation to participate along with artists Jean Dubuffet, Mark Rothko, Sam Francis, and others in an exhibition of contemporary painting entitled "Art and Contemplation", held at Palazzo Grassi in Venice, he created a series of 22 works dedicated to the lagoon city.

[17] The works consisted of large sheets of shiny and scratched copper, pierced and gouged, cut through by dramatic vertical gestures that recall the force of New York construction and the metal and glass of the buildings.

[9] Another work from that time, Trinità (Trinity) (1966), consists of three large white canvases punctuated by lines of holes, embraced in a theatrical setting made from ultramarine plastic sheets vaguely resembling wings.

[7] In the last years of his career, Fontana became increasingly interested in the staging of his work in the many exhibitions that honored him worldwide, as well as in the idea of purity achieved in his last white canvases.

[13] At Documenta IV in Kassel in 1968, he positioned a large, plaster slash as the centre of a totally white labyrinth, including ceiling and floor (Ambiente spaziale bianco).