Councils with the lowest quality adult social care services in the country were named and shamed by regulators today.
The Care Quality Commission (CQC) said those that were not up to scratch now faced closer scrutiny.
One in four councils were rated as only adequate in terms of giving people choice and control over their care.
The CQC found that a third of councils need to do more to do in terms of caring for people with dignity and respect.
Too many councils were purchasing a significant proportion of residential and nursing home care from providers rated as poor or adequate and, in care homes for older people, one in five providers failed to meet the standard on social contact and activities, the CQC said.
Care Services Minister Phil Hope said that while the vast majority of care homes and councils were excellent or good, there was "a need for change".
He said plans for a National Care Service would create a system that was "simple, fair and affordable for everyone".
But Tory shadow health minister Stephen O'Brien said the Government needed to introduce higher standards and be tougher on "unscrupulous care home owners".
Liberal Democrat health spokesman Norman Lamb added that such homes should face closure unless urgent improvements were made, saying it was "scandalous" and "disgraceful" that standards of dignity and respect for residents in care homes have fallen in the past year.
In its first major statement on the quality of adult social care in England, the CQC told the eight councils rated as only "adequate" they must make improvements a priority.
They were: Bromley, Cornwall, Peterborough, Poole, Solihull, South Tyneside, Southwark, and Surrey.
All eight will receive greater scrutiny from the CQC and practical support from the Government, the CQC said.
A total of 16 councils - who have not been named to avoid giving them advance warning - were also selected for "in-depth service inspection on the basis of concerns about performance, gaps in its evidence or the length of time since the last service inspection", the CQC said.
The CQC also looked at the performance of 24,000 care homes, home care agencies, nursing agencies and shared lives schemes and found one in six providers were only poor or adequate.
It said concerns that councils may spend less on social care during tough economic times appeared to have eased, but added the CQC would be watching the situation closely.
"The consequences for individuals, carers and families can be damaging and distressing," it said.
Referring to today's report, CQC chief executive Cynthia Bower said: "Those affected should be absolutely clear that we will be very persistent in ensuring they take action in the run up to registration and afterwards, using all the new powers that will be at our disposal.
"I want to see the regulator and councils working in tandem to drive poor quality care out of the market."
But Southwark Council, which dropped from "excellent" to one of the eight worst in the country, dismissed the CQC reports as "flawed" and "inaccurate" and called for an urgent parliamentary review of the regulator.
Annie Shepperd, the council's chief executive, said the regulator had got it wrong and was undermining public confidence.
"We have no confidence that CQC have got this right," she said.
"If we were to start changing what we do based on their findings, we believe that we could be making some serious errors, potentially to the detriment of our elderly and vulnerable people."
The CQC assessed adult social care services in 148 English councils on seven factors - improved health, quality of life, positive contribution, choice and control, freedom from discrimination, economic well-being, and maintaining personal dignity and respect.
Peterborough Council was rated "poor" - the lowest rating possible - in terms of dignity and respect, but rated well in five of the categories and adequate in the other.
Denise Radley, the council's director of adult social services, said "good progress and improvement" had been made since the assessment, which looked back at 2008.
Poole Council, which was rated poor in terms of dignity and respect, adequate in two categories, and well in the four others, also said "significant improvements" had already been made.
Despite its low rating, Cornwall Council - which rated adequate in five categories and well in two - insisted it had improved and would continue to improve over the next four years, but conceded: "We clearly have some way to go."
Solihull Council, which rated adequate in four categories and well in three, said it took the need for improvement "seriously" and added it was "utterly committed" to improving services for the community.
South Tyneside Council, which rated adequate in four categories, well in two, and excellent in one, said it welcomed the support to help it "move forward with our modernisation of adult social care".
Bromley Council - which rated adequate in four categories and well in three - blamed an increased demand for longer waiting lists.
But it made no apology for "taking a measured approach in our planning to delivering the Government's agenda to radically change how adult social care is delivered".
The CQC also said 95 per cent of local authorities were rated as either excellent or well in the year to March 2009, compared with 87 per cent of councils last year.
It was now time to "strive for a higher standard", with tougher enforcement powers to "drive poor care out of the market", the regulator said.