BBC News' Kim Catcheside reports on the criticisms

It says young people are too often moved from carer to carer, causing emotional and social disruption.

Research suggests young people who have been moved around many times in their lives have low levels of educational achievement and face problems getting a job in later life.

According to recent government figures, there are 55,300 children in care in the UK.

Children in care often lack stability, says the report

The survey also found that services for children with disabilities and mental health problems were often inadequate.

A previous report by the Audit Commission on health authorities and children's mental health found care was often a lottery, with some areas spending up to seven times more per child than others.

The Mental Health Foundation, which estimates that one in five children will suffer from a mental illness, has also been critical of the standard of care being offered to young people.

It says government pledges of £84m for mental health services for children will not be enough to meet a shortfall caused by years of underfunding.

Disability charities have also pointed to inconsistent provision of services across the UK.

The new SSI/Audit Commission report, Getting the Best from Children's Services, urges councils to improve co-ordination with other agencies, such as health authorities and voluntary agencies, to improve services.

Andrew Foster, controller of the Audit Commission, said: "Too often initiatives designe dto improve quality are working in isolation of wider council services and the activities of other agencies."

The government's new policy for social services, Quality Protects, aims to improve services, for example, by encouraging greater cooperation between agencies and emphasising consistency and stability in services for children in care.

Listening

The Audit Commission's and the SSI's annual report on their joint reviews, Making Connections, published to coincide with the children's services report, is also critical of social services departments.

It found five - Calderdale, West Sussex, Sheffield, Bury and Coventry - were not serving people consistently well.

It urged councils to listen more to clients, understand their costs better and set clear targets.

It also states that there is "no clear link" between how well a council runs its social services and its budget.

Hard-pressed inner city departments were just as effective as richer rural ones, it stated.

The report also found that many departments were failing their ethnic communities.

It says: "Many councils are not responding effectively to diverse communities."

Fewer than a third of users of council services said they felt religion, race and culture were taken into account.

Jabeer Butt of the Race Equality Unit said the results were not surprising.

He said there had been improvements since the 1980s, but many councils were failing to take the needs of ethnic minorities into account, meaning they felt effectively excluded.

He added that black and Asian social workers were also not getting the support they needed when they were appointed.