Care groups are warning the government risks failing to deliver on a pledge to reform the funding system for the long-term care of elderly people in England.
In a letter to the health secretary, they suggest a commission has lost "momentum" and changes may not be put in place in this parliament.
They say the "major challenge" needs to be addressed.
The Department of Health says reform remains a government priority and the commission will report by July 2011.
Health Secretary Andrew Lansley set up the Commission on the Funding of Care and Support in July.
BBC political correspondent Norman Smith said despite numerous commissions, green papers and manifesto promises, successive governments have failed to reform long term care for the elderly.
The last attempt founded on the eve of the general election following uproar over Labour plans for a so-called death tax - a compulsory fee to pay for social care which could have been financed from the estate of a person after their death.
The letter has been sent by Jane Ashcroft of the English Community Care Association; Mary Bryce of Ceretas; Andrew Larpent from the National Care Forum; Mike Padgham, President, UK Home Care Association; Nick Sanderson from the Association of Retirement Village Operators; Ian Turner from the Registered Nursing Home Association, and Nadra Ahmed of the National Care Association.
They say the deadline for the "presentation of agreed criteria against which options could be judged... has now passed, with no outcome".
"As representative bodies for providers across the social care spectrum, we see everyday the real problems for those seeking to access care in a system which is outdated, under funded and misunderstood.
"We welcome the requirement of the commission that it delivers a preferred option to government, bringing the prospect of real change in the medium term... We urge the commission to maintain the momentum established by the Secretary of State, and to ensure that this major challenge faced by our society is addressed."