The major parties are urged to support its public service agenda.
Acevo has been attempting to get the issue of the third sector's role in delivering public services onto the political radar at this year's party conferences, with varying degrees of success.
"With respect to public service delivery, the relationship between the sector and the Government remains in its infancy," says Nick Aldridge, director of strategy and communications at the chief executives body.
"No government in this country can deliver truly responsive public services without involving the third sector."
Most politicians seem to agree that the third sector can play a significant role in public service delivery - and has already done so.
The differences between the parties are not about the basic principle but about the extent of the involvement of charities in service delivery.
This prompts comparisons between Acevo and the NCVO, which agree on the principle but disagree about scale and emphasis.
"The third sector can bring an entrepreneurial, innovative approach," says Martin Horwood MP, who spoke at the Acevo fringe meeting at the LibDem conference in Blackpool.
"I'm not arguing for a mass shift in services; I think there should be openness and flexibility."
Acevo makes its case to the Conservatives on 4 October, but if leadership contender Kenneth Clarke's comments at the Centre for Social Justice last week provide any indication, the Tories toe a similar line. Clarke advocated greater co-operation between the Government and the private and voluntary sectors on public service delivery, yet he added that the extent of the sector's involvement "depends on the quality of its services". "The Government should never evince hostility towards the voluntary sector," he said.
Acevo believes it is with the Labour Party that it shares the most common ground, but Aldridge wants to make it clear that this isn't a question of privatisation.
"It's about improving services and involving organisations with expertise," he says.
Winning too much support from politicians could make some voluntary organisations slightly nervous. At the TUC Congress earlier this month, a number of delegates warned that charities delivering public services risked making their staff into a "second-tier workforce".
But John Low, chief executive of the RNID and chair of Acevo, said he felt the RNID's successful involvement in managing the delivery of digital hearing aids, in agreement with the Department of Health, showed that voluntary organisations can strike a balance between entering into public service contracts and maintaining their freedom to campaign.
"If you have a working relationship with local authorities and the Government, it doesn't mean you should say nothing if things go wrong," he says.
- See Editorial, page 22.