During the Premio Marzotto 1958, an international exhibition for contemporary painting held in Valdagno, Munich and Paris, Cassinari exhibited three of his works; that exhibition was mounted by Jean Cassou, Kurt Martin and Marco Valsecchi. During a personal exhibition, which was mounted at the Bussola Gallery in Rome, Nello Ponente presented eighteen oil paintings that Cassinari created in the previous two years. Cassinari exhibited his works with Ajmone, Morlotti and Music at the Blu Gallery in Milan, with Morlotti at the Odyssia Gallery of Rome. 1959: Besides participating to the personal exhibitions at the Alberti Gallery in Brescia, at the Plastica Galeria de Arte of Buenos Aires and at the Sianesi Gallery of Milan, he also took part with five paintings in the permanent exhibition of Milan entitled 50 anni d’arte a Milano dal Divisionismo ai giorni nostri, which concerned the Milanese art during the last fifty years, and in the Documenta II held by Kassel. Cassinari was introduced by Franco Russoli at the VI Mostra Francia-Italia, an exhibition about French and Italian artists held in Turin and in that occasion he sold Estate (Summer) to the Modern Art Civic Gallery of the town. He exhibited five paintings, which were presented by Raffaele Carrieri, at the VII National Quadrennial Art of Rome at the Palazzo delle Esposizioni. Cassinari took part in many collective exhibitions, such as the Peintres et Sculptures du Futurisme à nos jours at the Musée d’Art et d’Industrie of Saint-Etienne, the 20th Century Italian Painting and Sculpture from the Estorick Collection at the South London Art Gallery, the Jahreausstellung mit italienischen Malern held in Darmstadt. In the same year he exhibited some of his works at the Pater Gallery of Milan with other artists, such as Ajmone, Birolli, Dova, Gentilini, Fontana, Morlotti and Scanavino.