Editorial to the Special Issue "Clinical Immunology in Italy, with Special Emphasis to Primary and Acquired Immunodeficiencies: A Commemorative Issue in Honor of Prof. Fernando Aiuti".

Fernando Aiuti (Figure 1), born in Urbino on 8 June 1935, suddenly died on 9 January 2019, leaving a great void not only among his family members and those who knew him and appreciated his great humanity and acute intelligence, but in the entire immunological scientific community [...].