This front facade was designed by Palladio and built from 1564 and finished in 1570. Palladio was only responsible for this facade of the church, as the original designer, Jacopo Sansovino, designed and build the building years before. The signifance of this facade is that is done in a style that Palladio would repeat in his other buildings, like Il Redentore. This style was unique in the way it connected the nave to the aisles. This information is taken from http://www.isevenezia.it/en/church-and-convent/church-the-facade.