Mr Berlusconi's new government will be Italy's 62nd since World War II
The new centre-right cabinet of Italian Prime Minister Silvio Berlusconi has been sworn into office as the country's 62nd post-war government.
Mr Berlusconi's line-up returns loyalists to posts held in previous governments and offers fresh faces.
Giulio Tremonti becomes finance minister for the third time, with the task of reviving the stagnant economy.
The 21 members of Mr Berlusconi's cabinet took the oath in Rome's presidential palace.
One by one, each minister pledged to: "be faithful to the Republic, loyally follow the constitution and laws and to carry out my role in the exclusive interests of the nation".
Mr Berlusconi has appointed members of both the People of Freedom party - a merger between his Forza Italia party and the post-fascist National Alliance (AN) - and the Northern League to key portfolios.
Correspondents say the new government's most pressing challenges include breathing new life into Italy's ailing economy and finding a solution to the untreated rubbish mountains in Naples.
NEW ITALIAN CABINET
Prime Minister: Silvio Berlusconi
Foreign affairs: Franco Frattini
Interior: Roberto Maroni
Justice: Angelino Alfano
Economy: Giulio Tremonti
Defence: Ignazio La Russa
Economic development: Claudio Scajola
Education: Maria Stella Gelmini
Agriculture: Luca Zaia
Environment: Stefania Prestigiacomo
Infrastructure: Altero Matteoli
Health and labour: Maurizio Sacconi
Culture: Sandro Bondi
Federalist reforms: Umberto Bossi
Mr Berlusconi's closest aide, Gianni Letta, returns to his previous job of cabinet under-secretary. Another aide, Sandro Bondi, will be culture minister.
"It's a mixed bag," said political analyst Robert Leonardi of the London School of Economics, commenting on the cabinet line-up.
"On the one hand there are a number of people who we've seen before - the usual suspects - but there are also a number of new people, some of whom are unknown quantities," he said.
He said Mr Berlusconi may well have to mediate between the competing forces of the Northern League, which doubled its share of the vote in April's poll and the National Alliance.
"In the past he has played the two off against each other by watering them down. Perhaps that will be more difficult now that [Northern League leader Umberto] Bossi is stronger within the coalition," Mr Leonardi said.
In the Corriere della Sera newspaper, columnist Massimo Franco writes: "He has created a government in his own vision and likeness, and this is a huge opportunity and responsibility."
Mr Bossi, the volatile, firebrand leader of the anti-immigrant Northern League, has been given the reforms portfolio.
Another senior Northern League official, Roberto Maroni, will be the country's new interior minister.
Their party colleague, Roberto Calderoli, whose provocative comments on Islam have sparked anger in Italy and Libya, has been made minister of "legislative simplification".
"They just invented a new ministry without portfolio to get him into cabinet without giving him anything delicate," Mr Leonardi said.
Mr Berlusconi kept his pre-election promise of including women in the cabinet.
The four minsters include former Equal Opportunities Minister Stefania Prestigiacomo, now in charge of the environment portfolio, and 31-year-old Giorgia Meloni, who will be in charge of youth policies.
He has also named former television showgirl Mara Carfagna minister for equal opportunities.