The campaign to promote women at the workplace, which enjoys the support of the Prime Minister, was "tired if not sick", according to the source.
The drive to persuade companies to introduce "family friendly" policies is incompatible with many organisations' obsession with reducing "head count", the source said. The longer hours demanded at work simply do not lend themselves to family responsibilities.
A growing number of companies have signed up to Opportunity 2000, which encourages organisations to set targets for the promotion of women, but progress within the signatory companies is slow and elsewhere barely exists. The recession and tougher management policies are making the situation worse rather better, it is argued.
One of the problems is that women do not want to be seen as a "special group". The source said that sensitivity on this issue was growing among women and was undermining the organisation's effectiveness. "Women are saying we don't want to be singled out,but we do want the situation to improve."
Some have suffered a "backlash" when they have been promoted in Opportunity 2000 companies, with male colleagues claiming they have been chosen because of their gender.
Opportunity 2000 has been able to attract most support from companies that have a disproportionate number of female employees and count women among their most important customers. Most of the big retail groups are members of the campaign, but male-dominated areas such as the police force and the print media are proving tough to crack. Despite the Alison Halford case, which drew attention to the discrimination women suffer in the police service, only three of the 43 regional forces have joined Opportunity 2000.
The source said: "The attitude [in the police] is that morale is low among the boys, let's do nothing to upset them.''
The source added: "It is important to get a critical mass of women into the decision-making process so that a more sympathetic approach can be developed."
Despite its difficulties, Opportunity 2000, which now covers one-quarter of the workforce, should be kept going to ensure the issues are kept in the public eye, the source said.
In November, Lady Howe announced that members had introduced a growing number of "family friendly" policies, but conceded one of the priorities was to monitor take-up rates.