Over the years, the defences against counterfeiting, initially aimed only at the production systems and printing techniques, also began to focus on incentivizing the police forces to act more incisively. International links were also important, especially the "International Convention for the Suppression of Counterfeiting Currency", which entered into force in Italy under Royal Decree 1518/1935.
During the Second World War, the establishment of a new banknote printing works in L'Aquila allowed banknotes to be printed in the same way. Production continued although more slowly and with great difficulties even after the bombing of December 1943, which practically destroyed all the machinery and claimed the lives of 3 men and 16 women.
While the printing works in L'Aquila were producing the latest series of banknotes and those for circulation only in Italian East Africa and in Albania, the State Printing Works' banknote section, which then had inadequate machinery, was exclusively producing the old kind of Bank of Italy notes designed by Barbetti.
From October 1943, the State Printing Works suspended all activities after the German Army carried away some of its Roland engraving machines and other printing materials to the Istituto geografico militare in Florence. The Printing Works in Rome began work again only in November 1944, following the liberation of the city by the Allied forces, after which the seized machinery was returned.
As a result of pressure from the Government of the Italian Social Republic, in October 1943 some of the offices of the Bank's Head Office were transferred to Moltrasio on Lake Como. The production of currency was outsourced to private companies, under the control of the State Printing Works and representatives of the State General Superintendency and the Bank of Italy.
In July1943, following the Sicily landing, the first issues of Allied Military Currency (AM lire) went into circulation with distribution increasing with the advance of the Allied forces.
In 1942 the Washington Bureau of Engraving and Printing had started a project to introduce paper money for the American occupation. In March 1943 the new banknotes were designed, and printing began in June by the Forbes Lithograph Manufacturing Company. The Bureau then overstamped the banknotes with the necessary details (face value, series, and country of use). On 24 September 1943, the regulations for the circulation and exchange of Allied Military Currency were published, establishing equal value for the allied banknotes and Italian lira notes.