The Chancellor won an enthusiastic response after repeatedly declaring that the Government had "only just begun" its crusade to create a "Great British society" which had won the war against child poverty.
"With the scale of the challenges ahead, there is no gain for our country in policies which look credible but are not radical - and fail to deliver," he said. "Nor, as we learned the hard way, can we ever succeed by posing as radical without being credible - and fail even to begin."
Mr Brown pledged that Labour would never take risks with inflation or let the public deficit get out of control. "We will not spend money we have not earned. Our years of responsibility in government have only just begun."
But in a conference debate on the economy, the Chancellor came under strong pressure to channel the Treasury's estimated pounds 10bn "war chest" into public services and to scrap plans for pre-election tax cuts.
John Edmonds, leader of the GMB general union, said: "If we have extra money in the next two years it certainly should not go on tax cuts. The priority must be to restore and expand our hard-pressed public services."
Dave Prentis, deputy general secretary of Unison, warned Mr Brown: "Change is not conjured out of thin air or the threat of insecurity." He attacked the Government's scheme to attract private investment in public services as "expensive, divisive and not value for money".
In his speech, Mr Brown demanded "responsibility from all", with employers investing and workers showing restraint on pay. In return, full employment was now within reach - "not jobs for life which no government can promise to deliver, but job opportunities for all throughout their working life".
He hinted at a further expansion of the New Deal programme for the jobless. Ministers plan tougher benefit penalties if claimants refuse to turn up for interviews at Jobcentres, and want to ensure more single mothers attend, although they do not intend to make this compulsory.
The Chancellor had a blunt message for both sides of industry, warning that companies and countries "which fail to adapt, reform and lead will simply be left behind." He promised an assault on "rip-off Britain" and to "expose and end anti- competitive practices." The Government would publish league tables comparing key charges for for financial services and stop the banks preventing small firms expanding.
"We must never again be a party that is seen as anti-success, anti-competition, anti-profit, anti-markets," he said. "Our enemy is not markets but monopoly, not competition but cartels, not profits but privilege and greed."
Mr Brown said that, while the Tories would prepare for a leadership contest at their conference next week, Labour was planning for a general election. Promising that Labour would be "credible radicals for the 21st century", he endorsed Tony Blair's "third way" philosophy - a phrase he has rarely used in the past.
Earlier Mr Brown sought to kill speculation that he hoped to succeed Mr Blair as Prime Minister. He said his job was to ensure stability, prudence and job opportunities. "That is my ambition, that is the job I am involved in doing, that is the job that I hope to be doing."
Mr Blair returned the compliment by hailing Mr Brown as "brilliant" and "probably the most able person in British politics" and said he could not have achieved what he had done without him.Reuse content