In Milan, Fassina graduated in architecture. He attended the Polytechnic University of the city. He initially dealt with industrial design. He was particularly interested in the design of consumer goods and exhibitions. It took some time for Giancarlo to discover his love of designing luminaries. At the age of 25, he began working with Artemide. In design and development, Fassina was not limited to a particular type, designed lamps for private and public spaces, as well as for international exhibitions, e.g. In Milan and the Fossati Theater. From the 1980s onwards, he made a name for himself through his radical art. He was also called "avant-garde designer".