The implementation of the Compact has been "slower, patchier and less energetic than might have been expected", according to a historian.
Meta Zimmeck, a visiting research fellow at Roehampton University, said progress was "desultory" because the government had failed to take it seriously and, until recently, to provide sufficient resources.
Zimmeck said the Compact - the public and voluntary sector agreement that sets out how both sides will treat each other - had delivered "some positive outcomes" since it was signed by Tony Blair in 1998. But she added: "It is not possible, based on hard evidence, to pinpoint what these are."
Writing in the first edition of Voluntary Sector Review, she described the Compact as "a handsome facade with not much behind".
She said last year's refreshed Compact "does not remedy the opaqueness of the original version and indeed adds additional levels of obscurity".
Oliver Reichardt, head of Compact Voice, which represents the voluntary sector on the Compact, agreed that progress was initially slow but "over the past five years has been rapid".
"We now have many examples where the Compact has transformed areas and relationships for the better," he said.
A spokeswoman for the Commission for the Compact, which oversees the agreement, said it agreed with most of the article, but not all of it. "We think the refreshed Compact is a definite improvement on the original Compact and that it reflects what was recently negotiated and agreed between government and third sector representatives," she said.