[1] She began her career during her university studies (she graduated in pharmacy) at Tele Libera Firenze, a broadcaster in the Tuscan capital, at the end of the seventies, hosting the news, some quizzes and a forerunner of modern talk shows (Quattro chiacchiere con Cesara).
Having become very popular with Tuscan viewers, she wrote her first articles for the Florentine newspaper La Città, which belongs to Mauro Ballini, also owner of Tele Libera Firenze.
After having debuted the Italia 1 news program Studio Aperto with Emilio Fede, she was one of the founders, together with Enrico Mentana, Lamberto Sposini, Cristina Parodi and Clemente Mimun, of TG5, which she has hosted since its birth on 13 January 1992.
Her biggest scoop was on the occasion of the referendum of 18 April 1999 (question on the abolition of the proportional quota in the elections of the Chamber of Deputies), when late at night she interrupted her director Enrico Mentana in the studio, being the first to announce that the quorum had not been reached, which had been taken for granted.
In 2006 she was suspended for six months from the Lazio Order of Journalists, after the revelation of telephone interceptions by the Potenza prosecutor's office: the public prosecutor Henry Woodcock had discovered that the journalist recommended the entrepreneur Ugo Bonazza to the minister of the environment Matteoli to unblock a Monopoli case, negotiating over the phone a fee of 10,000 euros (Buonamici later denied to the magistrate that she had ever actually received them).
In the 2023-2024 season, during her experience as a commentator on the seventeenth edition of Grande Fratello, she aroused a considerable level of criticism due to her constant tendency to oppose Beatrice Luzzi during the reality show.