Within the program of the XII Iberian Docomomo Congress held in Valladolid from September 27 to 29, 2023, the presentation of the communication “The most beautiful rationalist façade in Seville: José Galnares Sagastizábal and the Ybarra building” has been made. This communication includes, in the words of its authors, Pablo M. Millán, Antonio Huertas and Germán Reyes, the work of the Sevillian architect, an example of rationalism in the context of the avant-garde.