The Conservative leader has launched a scathing attack on Gordon Brown, claiming the government has failed the "four million" facing "problematic debt".
In a speech to Chance UK, a charity working with vulnerable children, David Cameron claimed the economy was richer while families were poorer under a Labour government.
He urged: "It is time for change when after ten years of a government that promised social justice, there are 600,000 more people in deep poverty than when they began."
One option for those struggling to cope with problematic debt is an Individual Voluntary Arrangement (IVA).
Thrifty Scot, an online financial advice resource, says there are many advantages of such an agreement, including being able to reduce debt by as much as 70 per cent.
Debtors who enter into IVAs can no longer be chased by debt companies and are means tested to assess at what rate they can afford to make repayments, it reports.