Enzo Mari - author of Structure 731 of 1963 - is considered one of the most important designers of the twentieth century, also conducting research on the psychology of vision and the methodology of design. In 1962 Mari took part in the exhibition “The responsive eye” which gives shape and definition to the trends that deal with kinetic, programmed and optical art. Structure 731 represents one of the most emblematic works of op-art and kinetic art: made up of 400 square spaces within which as many square plastic shapes are embedded, at different depths. In her Dynamic Structures, among the most intense and significant works of the period of adherence to programmed and kinetic art, Mari uses modules varied only in color to experiment with her proposals for serial and dynamic programming. The design method is based on modular prefabricated elements and the use of poor materials - such as wood, aluminum, plastic - that allow for ease and great communication effectiveness.