Luigi Moretti, one of the protagonists of twentieth-century architecture, was a gifted designer of outstanding creativity. He was also a scholar and a man of broad culture and deep sensibility. Luigi Walter Moretti was born in Rome to Maria Giuseppina Moretti and Luigi Rolland. According to members of the family, the birth occurred on 22 November 1906, but was only registered on 2 January 1907. In 1925, four years after his father’s death, he enrolled at the School of Architecture in Rome, where he graduated in 1930 with the highest honors. Until 1934, Moretti was teaching assistant to Vincenzo Fasolo and to Gustavo Giovannoni. Moretti he began to practice while he was still a student. Together with Enrico Vallini, a colleague of his father, he designed a number of buildings. In 1933 he was appointed director of the technical department of the Opera Nazionale Balilla (ONB). During these years he participated in the major architectural competitions promoted by the Fascist regime: the Palazzo del Littorio (1934 and 1937) and the E42 quarter’s Piazza Imperiale (1937). After the end of WWII Moretti resumed his practice in Milan. At the time he was involved in the design of twenty-two apartment buildings with included communal services, and built the office and residential complex in Corso Italia in Milan (1949-1956). In 1950, Moretti founded and directed the arts and architecture magazine Spazio. Following the seventh issue that came out in 1953, the periodical suspended its publication. The Spazio gallery in Via Cadore 23, Rome, was also short-lived (1954-1955), yet succeeded in consolidating the links with the art critic Michel Tapié, the predominantly French Autre artistic milieu and the young Roman painters. The interest in mathematics, formal logic and scientific disciplines re-emerged during these years with the foundation in 1957 of the IRMOU (National Institute for Mathematical and Operational Planning Research), the development of the theory of “Parametric Architecture”, formalized and presented in 1960 on the occasion of the XII Triennale. In 1960 Moretti began the design of the residential district INCIS at Decima, Rome (1960-1965), and the Watergate residential quarters in Washington. Moretti had arrived in the USA as a consultant to the Società Generale Immobiliare for which together with Nervi he designed the Montréal Stock Exchange Tower. Moretti’s interests in the configuration of structural elements and in their spatial representation emerged in many projects from mid-Sixties onward. Luigi Moretti died on 14 July 1973.