A judge has bemoaned the folly of separated couples running up "completely disproportionate" lawyers' bills fighting over money in family courts.
Mr Justice Holman says "week after week, if not day after day" family court judges see people who have allowed legal disputes to get "completely out of control".
And the judge, who is based in the Family Division of the High Court in London, says the "tragedy" is that if people learn their lesson, they learn it too late.
He raised concerns in a ruling on a case involving a separated couple arguing over how much maintenance the man should pay for their child.
The judge said the difference between the pair, who were not identified, was about £4,000 a year.
But he said the woman alone had already run up legal bills of £30,000.
He said the dispute "cries out for settlement".
"Week after week, if not day after day, judges like myself see litigants spending completely disproportionate amounts of money on purely financial litigation," said Mr Justice Holman.
"The tragedy is that any given couple or family tend only to experience such waste and folly on a single occasion, and if they learn the lesson at all, they learn it too late."
He added: "This case seems to me to be yet another example of parties who have allowed their litigation to become completely out of control and to lack any proportionality to the underlying sums in issue."
The judge said there was always a correlation between amounts at issue and costs being incurred.
"Any person approaching this case with the least detachment, sense of reality or costs proportionality, would ask how it is that these parties are still litigating against each other with such bitter intensity," he said.
"The bald fact is that the dispute between them in relation to current levels of maintenance is now £4,000 a year, and to get to this point, and to achieve enforcement of arrears, the mother has already herself spent £30,000."
He added: "To my mind, there is a total loss of costs proportionality in this case."