On the eve of a vote in the European Parliament that is expected to approve all 19 members of his team, Mr Prodi promised more "glasnost" in Brussels. He called for a doubling of the number of EU member states and firm start dates for expansion to the east.
Ahead of today's vote, some centre-right MEPs were still targeting Philippe Busquin, the Belgian commissioner-designate for research, who has faced intensive questioning over his role in the scandal-hit Belgian socialist party.
After Mr Busquin and Mr Prodi met for talks yesterday, the incoming president of the Commission threw his weight behind his Belgian colleague, while promising to be "very, very severe" in examining any further revelations. Mr Busquin, who was president of the Belgian socialists when the Agusta- Dassault cash-for-contracts scandal broke, has promised to resign if any formal charges are laid against him.
The 36 British Conservatives will vote today against the Commission, claiming that 11 of its incoming team are unfit for office. However, their stand looked isolated in the centre-right bloc, which now dominates the parliament.
Mr Prodi's allies believe Mr Busquin is safe pending further developments, while the centre-right thinks it has put down a marker for the future by showing Belgium's incoming commissioner the "yellow card".
The parliament cannot veto individuals, although it has the right to vote down the entire Commission. However, throughout hearings for all 19 individual commissioners, criticism from MEPs has split along party lines, tending to neutralise itself.
While the centre-right has put the spotlight on Mr Busquin, the Socialists have raised questions over Loyola de Palacio, the formidable Spanish vice- president designate, who once served as Spain's agriculture minister. Questioned over farm fraud that took place while she was in office, Ms de Palacio resisted attempts to pin her down on the circumstances under which she would quit, provoking indignation among left-wing MEPs.
Given the disaster of last March when the Jacques Santer-led commission resigned en masse, the spectre of sleaze has hung over the approval process. But, while questions have been raised over Mr Busquin, Ms de Palacio and Mr Prodi himself (over past business dealings in Italy), MEPs have failed to land a killer blow in the form of new evidence.
That should see Mr Prodi today enshrined at the head of a team which is stronger than that of his predecessor and which concentrates its fire- power on his highest priority areas - foreign policy and economics.
The four-strong team of foreign relations commissioners includes three formidable heavyweights, including Chris Patten, the former governor of Hong Kong, who won over MEPs at his hearing with a faultless combination of flattery and detailed exposition on foreign policy issues.
Pascal Lamy, who holds the powerful trade portfolio, may have less international experience but knows Brussels better from his time as chief aide to the former commission president, Jacques Delors. Last week Mr Lamy proved his astuteness by poaching a top British official as the deputy head of his cabinet (private office).
Then there is Gunter Verheugen, who finally won his reward for years of service in the German Social Democrats with the post of commissioner in charge of EU enlargement.
How the formidable egos of Messrs Patten, Lamy and Verheugen will co- exist, not only with each other but with the member states' new foreign policy supremo, Javier Solana, remains to be seen.
But most striking is the new presidential style of the structure Mr Prodi is building. Bolstered by new powers from the Maastricht and Amsterdam treaties, the former Italian premier can reshuffle his team's portfolios and has extracted a pledge from each incoming commissioner that they will resign if he asks them to.
With the backing of member states, appalled at the vacuum left in March, Mr Prodi is now determined to exploit his leverage to create a powerful new commission. As one senior diplomat put it: "The member states have decided to back a strong commission. They realise that if it loses power, it seeps to the parliament rather than national capitals."
His message is one of reform, with a programme of change in Brussels led by Neil Kinnock, designed to win back public confidence. Mr Prodi told MEPs he is planning "to make a register of my correspondence available for public inspection" and said that "transparency is vital for the democratic health and accountability of the EU".
Mr Prodi told MEPs in Strasbourg that it was not in their interests to have a commission which acted as the "secretary" to the Council of Ministers. He promised to present an annual report on the "state of the union" and staked a claim to shaping the future of the EU in a way his predecessor never dared. "We are," he said, "going to enlarge the European Union from 15 to 20 to 25 to 30 member states."
Mr Prodi called for discussion at December's Helsinki summit of a "firm start date" for the next wave of countries due to join. He also rejected the idea of a two-stage discussion of the internal reforms needed to prepare the EU for enlargement as "particularly unappealing".
Both messages will be unwelcome to the more cautious Finnish presidency of the EU. As one MEP put it: "We could be in for a bumpy ride."
KEY PLAYERS IN THE `ZERO-TOLERANCE' COMMISSION
Pascal Lamy (France)
Puritanical and clever, the balding Mr Lamy once effectively ran Brussels as chief aide to Jacques Delors. Despite the many skeletons stored in his cupboard, Mr Lamy emerged unscathed from his parliamentary grilling. Few people know better how the EU works.
Loyola de Palacio (Spain)
Made her name as an outspoken agriculture minister, but her past has returned to haunt her. Socialist MEPs criticised her over farm scams which took place while she was in office in Spain, and she was reluctant to vow to quit should her new duties go badly.
Chris Patten (UK)
Dubbed "Fatty Pang" by the Chinese when he served as the last British governor of Hong Kong, Mr Patten is an experienced operator. He is expected to be a star of the new Commission and to clash with the trade commissioner, Mr Lamy.
Philippe Busquin (Belgium)
According to centre-right MEPs, Mr Busquin, a former physics lecturer, is the bad boy of the present batch. He has faced questions over his role in the scandal-hit Belgian Socialist Party, and the centre-right claims he has misled parliament.
Neil Kinnock (UK)
The former Labour leader who took on Militant in Britain now finds himself with an even bigger task: creating structures for a `zero-tolerance' Commission. The staff unions that dominate Brussels are ready for a rematch of Kinnock versus Derek Hatton.
Frits Bolkestein (Netherlands)
After years parading as a sceptic, this former executive with Shell has re-invented himself as a newborn European. He has expressed horror at being likened to Michael Portillo, John Redwood or Charles Pasqua. But, most MEPs concluded, who wouldn't?
Gunther Verheugen (Germany)
He has landed a plum job despite having criticised his new boss, Romano Prodi, just two weeks earlier. A career SPD politician who ended up as Germany's ex-foreign minister, Mr Verheugen is regarded as one of the heavyweights of the new team.
Margot Wallstrom (Sweden)
A journalist turned politician, Ms Wallstrom stands out as one of only five women in a team of 20. She quit her post as social affairs minister, taking her family to Sri Lanka, and has so far displayed a firm grasp of her portfolio and impressive political skills.