The two houses together form a perfect bicameral system, meaning they perform identical functions, but do so separately.

Furthermore, a small number (currently 5) serve as senators for life (senatori a vita), either appointed or ex officio.

Article 57 of the Constitution of Italy originally established that the Senate of the Republic was to be elected on a regional basis by Italian citizens aged 25 or older (unlike the Chamber of the Deputies, which was elected on a national basis and by all Italian citizens aged 18 or older).

For Italian residents, each house members are elected by single ballots, including the constituency candidate and his/her supporting party lists.

Voters can cast their votes in three different ways: In 2016, the Italian Parliament passed a constitutional law that "effectively abolishes the Senate as an elected chamber and sharply restricts its ability to veto legislation".

The palace takes its name from Madama Margherita of Austria, daughter of Charles V and wife of Alessandro de' Medici.

Later, in 1755, Pope Benedict XIV (whose coat of arms still dominates the main entrance) ordered major restructuring, entrusting the work to Luigi Hostini.

A radical transformation which involved, among other things, the modernization of the hemicycle, the full remaking of the prospectus on Via San Salvatore and Via Dogana Vecchia, and the establishment of a connection with the adjacent Palazzo Carpegna.

The small church of San Salvatore in Thermis, dating to the 6th century, which stood in the street to the left of the palace, was first closed, expropriated and later razed for security reasons.

A plaque on the wall behind the speaker's chair commemorates the king's address to Parliament when first convened in the new seat of government: Above this has been placed a plaque bearing the inscription: To the viewers' left stand the flags of the Italian Republic (with a ribbon embroidered with the words SENATO DELLA REPUBBLICA) and the European Union.