 Lorenzo Mattielli soon became a close friend of Antonio Beduzzi, who had quickly recognized his skills.They worked often together on the same projects, Beduzzi as painter and designer and Mattielli as sculptor.In the same way, he also worked together with the architect Joseph Emanuel Fischer von Erlach (Karlskirche, Imperial stables in the Hofburg, Schwarzenberg Palace, Reichkanzlertrakt in the Hofburg, Harrach Palace).