Three families have won an important legal ruling that the extra needs of disabled adults and children must be factored into housing benefit.
They brought proceedings against their local authorities and the Department for Work and Pensions, because their housing benefit did not cover their housing needs.
They argued that the rules discriminated against them because they were left in a worse position than the able-bodied.
The Court of Appeal said today that the regulations did discriminate against the disabled, because they did not allow for an additional room to be paid for where someone had a carer - or where two children could not share.
The proceedings involved the private rented sector, rather than the social rented sector, where people are allocated property on the basis of their assessed housing needs, including needs resulting from disability.
Two of the cases were brought by Ian Burnip and Lucy Trengove, whose action was pursued after her death in December 2011 by her mother, Rebecca.
Both needed overnight carers in their flats, but their housing benefit was quantified by reference to the one-bedroom rate which would apply to able-bodied tenants.
The third case involved Richard Gorry - two of whose three children have Down's Syndrome and spina bifida respectively and for whom it would be inappropriate to share a bedroom as able-bodied sisters would be expected to do.
The family has a four-bedroomed house but housing benefit is provided by reference to the three-bedroomed rate which would apply if the girls were not disabled.
Since the litigation began, the rules have been amended to cover the circumstances of Mr Burnip and Ms Trengove, but not that of Mr Gorry.
Heading a panel of three judges, Lord Justice Maurice Kay, vice president of the Court of Appeal, Civil Division, said that the Secretary of State had failed to establish objective and reasonable justification for the discriminatory effect of the statutory criteria.
He said: "Disability can be expensive. It can give rise to needs which do not attach to the able-bodied and Ian Burnip and the late Lucy Trengove provide stark examples".
Mr Burnip's solicitor, Polly Sweeney, of law firm Irwin Mitchell, said later: "This judgment has widespread implications for policy-making and is crucial to promoting equality for disabled people and assisting them to live independently.
"Whenever the Government introduces new policies, or reviews existing policies, they now face a duty to ensure that appropriate provision is made for disabled people to ensure that discrimination does not occur."
Mr Burnip's mother Linda, who set up the Local Housing Allowance Reform Group to campaign for changes in the system, said: "Winning this case reinforces disabled people's right to not be discriminated against within the benefits system and also affirms their rights under the UN Convention on the Rights of Persons with Disabilities.
"We hope that the case will help other disabled people who feel that they have been discriminated by government policies and law".
Alison Garnham, chief executive of Child Poverty Action Group, which represented Richard Gorry, said: "We welcome the fact that the court has recognised the unfairness of the housing benefit rules. This is a tremendous victory for the rights of disabled people and their children.
"In this case it was clearly not possible for two children, one with spina bifida and another with Down Syndrome, to share a single bedroom with such different demands and needs. It's absolutely right that the housing benefit system should respond to challenges like this, and it is clear discrimination if it does not.
"Disabled people and their families and carers are being assaulted by a series of unjust and arbitrary cuts. This ruling goes some way to mitigating the effects of the cuts, but children and adults are still being made the unfair target of the coalition's austerity agenda."
John Wadham, general counsel for the Equality and Human Rights Commission, said it was a "common sense ruling".
"Our intervention in the Burnip case has helped to ensure that all disabled people claiming housing benefit do not face indirect discrimination.
"If it was not for the Human Rights Act, disabled people may be more likely fall into rent arrears because they cannot afford the home that meets their needs and then face eviction.
"The rulings underline our analysis of the Government's 2010 spending review, published yesterday, which looked at potential effects of those decisions on women, ethnic minorities and disabled people.
"It calls for the development of a common model of analysis to predict the likely equality effects of policy and earlier use of the equality duties to ensure better targeting of funds and greater value for money."