Consumer groups will be given a greater role in identifying and fixing "broken markets" under plans set out by Ed Miliband for a shake-up of the way competition across the business world is regulated.
The Labour leader said he would legislate to ensure Which? and Citizens Advice would be given a say in setting the agenda of the Competition and Markets Authority.
He said Labour would be "the party of the consumer" and the plan for an annual competition audit of the economy would help ensure that areas where regulators were failing would be identified and tackled.
Appearing on BBC1's Andrew Marr Show he said: " Unless you bring the consumer into the heart of these things, we are not going to get the change we need, we are not going to get the change we need, we are not going to shine the light on these broken markets."
He added: "The Competition and Markets Authority scrutinises competition across the board. They will be working with Which?, the CAB and others to say 'where are the areas where competition isn't working, what are your members telling you about where we need to act?'
"They will be sending a report to Parliament and it will be framing the work for the year ahead."
Mr Miliband has already promised action to reform the energy sector, including a freeze on bills if he wins the 2015 election, and last week set out measures to promote competition in banking.
Shares in the predominantly state-owned Royal Bank of Scotland and Lloyds came under pressure after Mr Miliband unveiled his plans to break up Britain's big five high street lenders.
The Labour leader said: "Share prices go up and down but what really matters for the economy is getting the banking system right for the future."
Bank of England Governor Mark Carney told MPs before Mr Miliband set out the details of his plan that capping the banks' market share would not lead to a "substantial improvement" in competition.
But the Labour leader said: "He, to be fair to him, was asked about my speech before I made my announcement. He made the point that simply a market share for banks on its own isn't enough, he is right.
"We also need greater portability of accounts, businesses and individual customers being able to move their accounts around more easily, that's really important for proper competition.
"So he is right about that, it's got to be a whole set of changes to make our banks work for our businesses rather than our businesses working for our banks, which is what so many of our businesses in this country feel they are doing at the moment."
Mr Miliband said he wanted to see the deficit eliminated in the next parliament, but there were "fairer choices" that could be made about achieving that.
"We do want to see that happen, yes," he said.
"What we've said, we want to get the current account into balance by the end of the next parliament, we want to see debt falling. They are important things that Ed Balls has said."
But he added: "I f we come to office after 2015, there won't be lots of money to spend, things will be difficult. That's partly why the proposals I have on the economy - competition policy, banking - they are so important to change things.
"Because the task for the next Labour government will be to earn and grow our way to that higher standard of living, not being able to engage in lots more spending."
Pressed on whether the 50p rate of income tax for high earners would be reinstated, he said: "We want a fairer tax system and, as you would expect from an opposition, we will set out our plans in due course."
Asked about the controversial Channel 4 TV programme Benefits Street, Mr Miliband acknowledged there was an issue around a minority who refused to work, but insisted it was wrong to "demonise" people on benefits.
He said: "There is an issue about a minority of people who could work, but aren't doing so. That's why Labour has clear plans to say to every young person who has been unemployed for more than a year that they need to go back into work, and we'll make sure they get a job, and every older person unemployed for more than two years.
"But ... I don't think we should demonise every person on benefits. I think there are lots of people who are looking for work, who are desperate for work and who find that Britain is in the midst of a massive crisis of being able to find work in some places, a big cost of living crisis that our country faces.
"That's why we are talking about the big changes that we need in our economy to put those things right.
"I think we need big change in our country. When I talk about the cost of living crisis it's not just about the squeeze on wages, it's about insecure work, it's about the prospects to people's kids, it's about whether you can get houses at affordable prices.
"So there's big change that our country needs, I'm not going to settle for the status quo. We need that big change and that's what our plans are about."
Labour highlighted the energy market, banking and pubs as areas where there were problems for consumers.
Mr Miliband said " too often regulators have been captured" by the industries they were supposed to be overseeing.
The Opposition will challenge the Government in the Commons this week over the relationship between large pub companies - pubcos - and licensees.
Labour has called a debate on Tuesday to back calls for a statutory code to regulate the relationship, which it argues would help create a market which would benefit consumers, small brewers and landlords.
Which? executive director Richard Lloyd said his organisation would welcome closer co-operation with the authorities.
He said: " Markets that work for consumers are good for growing businesses, for innovation and for driving sustainable growth in the wider economy.
"With trust in essential markets at rock bottom and millions still feeling the financial squeeze, there is much to do to put the consumer at the heart of policy-making.
"Which? already works with the competition authorities, and we would welcome a closer relationship to help set clear priorities for competition, consumer protection and market reform. We look forward to seeing more detail on how these proposals would work in practice."
But the Confederation of British Industry warned against interfering with the Competition and Markets Authority's independence.
Katja Hall, the CBI's chief policy director, said: "The role of the Competition and Markets Authority is to act as an independent body that judges how effectively markets are working for businesses and consumers. It should operate free from interference and not be told how do its job by other stakeholders.
"Boosting choice and competition in markets is the best way to ensure business and consumers get a good deal. We look forward to seeing more detail on how the Labour proposals would work in practice."
Business Minister Michael Fallon told BBC1's Sunday Politics: "We are the party of competition and this (Labour) is the party by the way that fused HBOS and Lloyds together, that brought them together, that's given us some of these problems.
"Look we've already got now an annual competition review going on in the energy companies and we're already tackling banking by making sure that banks don't get into the trouble that they did under their policies.
"What's interesting about his proposal is it's the smaller ones who are less sure about this. It's the smaller banks like Metrobank who think this could actually inhibit their growth and it's the smaller energy companies who think through interfering with the market through his price freeze and so on he's actually going to hinder competition rather than stimulate it."