On Monday the president of the Madrid region, Esperanza Aguirre, unveiled the Pritzker Prize-winning architect as the lead designer of the new Justice Campus in the Spanish capital's Valdebebas Park.
Foster has been asked to draw up proposals for the first two buildings on the site - part of a plan to bring together all 19 of Madrid's courts onto one plot in the heart of the city.
According to reports, Foster described the project as 'bold and symbolic' and said that he would refer to the values of 'democracy and transparency' throughout the design process.
It will not be the first time Foster, who is married to Spaniard Elena Ochoa, has worked in the city. His practice is currently masterminding the design of the new 34-storey headquarters building for petroleum giant Repsol on the site of the former Real Madrid training ground.