Giovanni Battista Quadro (Quadrio), Italian architect, active in Poland. He came to Poland by way of Silesia, and he is first mentioned in a contract that he signed on 3 March 1550 with the Poznan Town Council for the reconstruction of the Gothic town hall, which had been severely damaged by fire in 1536. In 1552 he was appointed town architect and commissioned to design and build an extension (1552-55) to the Town Hall, which was finally completed in 1560. It was Quadro's masterpiece. Quadro held his post at Poznan for nearly 40 years. He erected many municipal buildings and town houses, favouring the use of brick and plaster and decorating the elevations and interiors with stucco, sgraffito and polychromy. Between June 1569 and April 1572 he worked with Giacomo Parri (d. 1580) on a new wing for the Royal Castle in Warsaw (lower floors destroyed 1944; restored 1971-84). //