The Vienna Convention of 24 April 1963 states that consular relations between States are established by mutual consent, and defines the status and functions of the Career Consular Officer and of the Honorary Consular Officer.
Career consular officer
Is to all effects a diplomatic agent, sent by his country to another State to carry out purely consular functions.
The Career consular officer enjoys a number of privileges (see 1963 Convention). He is entitled to a vehicle having a CC registration plate and to the immunity of the entire consular office.
Honorary consular officer
He is not an “envoy”, but a citizen of his own State of residence, chosen for special merits by a foreign State to act in a capacity as honorary Consular officer.
He thus performs, firstly, his own business activity/profession and, secondly, a consular function. He is not paid for this activity, and does not enjoy the privileges or immunities granted to the Career consular officer. Immunity is limited to consular archives and documents.
Exequatur and functions
With an Exequatur (from the Latin: let it be executed), the State of residence (in this case Italy) accepts and recognises the nomination of the chosen consular officer (career or honorary) and authorises him to exercise the vested powers.
The two consular categories differ more in terms of status than the functions actually performed, except for some functions exclusive to the Career consular officer. Both Career consular officers and honorary consular officers assist and protect citizens of the State they represent, help to promote trade and business between the two States and develop and further cooperation.
Specific civil, notarial, administrative and judicial functions vary from consulate to consulate and from country to country.