Italians began voting Sunday on constitutional changes that proponents say would increase stability in a country known for its revolving-door governments.
The reforms would strengthen the premier's powers, trim the size of the legislature and transfer some authority from Rome to the country's regions.
Italy has had 61 governments since World War II. Critics say that's partly because its 1948 constitution limits the premier more than other Western governments do, reflecting a fear of dictatorship in the wake of Benito Mussolini's Fascist wartime regime.
Some of those voting for the reforms said they were unhappy with the status quo.
"After 50 years, it's right to change the constitution," management consultant Guido Fabri said as he cast his ballot at a high school in Rome's historic center.
Opponents of the changes say reforms are necessary but the proposal was shoddily conceived under the previous conservative government of Silvio Berlusconi and would give too much power to the executive.
The changes would alter more than 50 of the constitution's 139 articles, representing the biggest-ever change the document.
The two-day referendum was also seen as a test of center-left Premier Romano Prodi's popularity two months after he narrowly won elections. Prodi objects to the changes. Berlusconi has urged citizens to approve them.
The reforms would allow the premier to dissolve parliament, a power now in the hands of the largely ceremonial president of the republic. The premier also would have the power to appoint and fire Cabinet members, decisions that the president now must approve.
Other measures, some of which would not take effect for years, include transferring authority over health, education and security from the central government to the nation's 20 regions.
The two houses of parliament, which currently have identical powers, would be given different responsibilities.