Systematic Progression of Simple Geometric Forms belongs to the portfolio GRAV. Groupe de Recherche d'Art Visuel 1960-1968, published on the occasion of the group's retrospective exhibition held at Lake Como in 1975, curated by Luciano Caramel. The portfolio was published by Zuco (Galleria Team Colore, Milan) and printed by Sam Villa, also in Milan, in an edition of 150 copies. It consists of six silkscreens, one by each member of the group: García Rossi, Le Parc, Morellet, Sobrino, Stein, and Yvaral. This is copy number 132. We only have 5 of the silkscreens from this portfolio.

Sobrino's composition is a grid of squares delimited by a green mesh, each one occupied by an inner square in red or blue of variable size. What changes from cell to cell is the proportion between the red inner square on a blue background or blue square on a red background. The variation is not random but systematic and traverses the surface in a progression that gives the work its title. The effect is a vibrating image in which the eye finds no rest because the relationship between figure and background constantly changes.

Francisco Sobrino, born in Guadalajara and based in Paris since the late 1950s, was one of the GRAV members whose practice focused most insistently on modular structures and systematic transformations of simple geometric forms, a line of work he maintained throughout his entire career.