To his considerable credit, Prince Charles has raised millions of pounds for charity. The Prince's Trust alone has returned £1.4 billion in benefits to society by helping more than 870,000 disadvantaged youngsters.
Such achievements are a proud symbol of a lifetime's work.
But now very serious issues about aspects of his fundraising have led to Charles facing a crisis, with his judgment being questioned.
By any measure, this could not have come at a worse time for Britain's next monarch. And, the brutal truth is that this calamity is entirely self-made.
Charles's friendships with foreign billionaires have long raised eyebrows – those holidays on Greek tycoons' yachts and his free use of a Texan financier's private jet, for example.
But his links with sleazy 'cash-for-access', as revealed by The Mail on Sunday over the past four weeks, risk becoming an indelible stain on the Prince's reputation.
To his considerable credit, Prince Charles (pictured last week) has raised millions of pounds for charity. The Prince's Trust alone has returned £1.4 billion in benefits to society by helping more than 870,000 disadvantaged youngsters
For it has been shown he has happily let wealthy foreign donors fund some of his most treasured projects and, on occasion, be promised help in securing an official honour.
Disturbingly, rather than manfully facing down the allegations himself, Charles appears to have allowed the staff involved to be thrown under the proverbial bus.
First, Michael Fawcett, his long-time confidant and the Prince's Foundation's chief executive, temporarily stepped aside. Then, amid mounting evidence of questionable practice, the charity's chairman Douglas Connell stood down and executive director Chris Martin temporarily stepped aside.
All three are tarred by irrefutable evidence that foreign tycoons were lured into donating millions to Charles's charities in return for meeting and dining with him, having rooms, benches and even forests and woods named after them on the Dumfries House estate, and – in the most serious cases – the promise of an honour and help obtaining British citizenship.
Most embarrassingly for Charles, Mr Connell went so far as to describe as 'rogue activity' and 'serious misconduct' the evidence that the Prince had agreed to meet a Russian banker and Saudi businessman in return for donations.
First, Michael Fawcett (left), his long-time confidant and the Prince's Foundation's chief executive, temporarily stepped aside. Then, amid mounting evidence of questionable practice, the charity's chairman Douglas Connell stood down and executive director Chris Martin temporarily stepped aside
Charles has denied any knowledge that his employees made such promises in return for money. But in doing so, rather than tackle the deeply damaging allegations head on, he has distanced himself.
In fact, it was stated on his behalf that the Prince 'is not involved in the governance of his charities' and that 'members of the charity executive team are not 'aides' to the Prince of Wales' but, instead, 'executives'.
Yet did he never ask why so many foreign magnates were clamouring for his favour? Did he never demand that rigorous due diligence was done with regard their business histories?
The Prince may have been blind to the perils, but Buckingham Palace courtiers have always disdained elements of his money-raising activities and have been shocked by a lack of transparency.
As Charles's biographer, I discovered that some close to the Queen were deeply concerned that, apart from the risk of having donors whose backgrounds were inadequately researched, the Prince was displaying signs of naivete.
Key among those voices was Prince Philip's. He agreed with senior Palace aides who were worried about the perception that his son was party to a 'rent-a-Royal' scheme. But Charles ignored his father's warnings.
A reluctance to take advice, though, has always been the Prince's way. Meanwhile, his relationship with Mr Fawcett, his indispensable aide-turned-'executive', has jeopardised his reputation.
Perilously close to dismissal twice – for example, over allegations that he sold off royal gifts (he was cleared by an internal inquiry of any financial misconduct) – Fawcett has always survived.
Royal biographer Tom Bower is pictured
Some might praise Charles's loyalty. However, I know I am not alone in seeing it as misplaced and ill-advised. Judge a man by his friends – and passions – is a well-worn but justified phrase.
Undoubtedly, Dumfries House is his passion. He bought the 1750s, Palladian mansion in 2007 and it needed millions to refurbish it.
But this was an immense challenge for a man who has always spent more money than he could raise and who has refused to accept advice to save cash by forsaking one of his six large homes.
Though lacking in self-knowledge, it is surprising that an intelligent man who is sensitive to many matters seems reluctant to ponder the contrast between his concern for the disadvantaged and his own personal extravagance.
He is not helped by sycophantic staff. Fawcett once told a charity donor: 'His Royal Highness lives modestly. He hasn't got a yacht and doesn't eat lunch'. In truth, aides know very well that unwelcome advice risks dismissal.
Too often, Charles has exploded with anger when told a home truth. Accordingly, no one dared warn him not to buy Dumfries, although its restoration required accepting money from dubious sources.
When advised on one occasion by an accountant that a proposed design was unaffordable, 'because you haven't got the money', Charles, I'm told, said to an assistant: 'I never want to see that man again!'
With such belligerence and only a rudimentary understanding of household management, Charles's latest troubles began.
Despite the Queen's opposition to his use of Buckingham Palace to raise money, Charles identified dates when his mother would be in Scotland and asked Fawcett to invite as many as 120 guests to Buckingham Palace to drum up money for Dumfries House and other charities.
At one such party, after wealthy Americans were given a private tour of the State Rooms, the Prince made a speech in which, cheekily, he declared: 'When the cat's away, the mice will play.'
In the Queen's opinion, her son blithely ignored the inviolable requirement to put boundaries between his work for charities and his position as future king in which impartiality is absolutely crucial.
That said, the results of the money-raising on his behalf were spectacular. Charles has raised in excess of £300 million over 20 years to fund his charities and buildings.
The Prince may believe raising money for good causes is a moral commitment that trumps everything – but it has come at a huge price.
Charles has survived repeated scandals because, with his mother's robust health, the idea of Charles III has been a distant prospect. But with Prince Philip's passing and the Queen celebrating her 96th birthday next year, it will become a reality sooner or later.
No one should be in any doubt: Charles's position is precarious.
His plight is compounded by his brother Andrew finding himself subject to a claim of sexual assault on an underage girl, and his son Harry writing a memoir that's expected to illustrate what he has described as a 'lot of hurt' between himself and his father.
Now, as never before, the spotlight is trained on the man who will be king.
Notorious among his staff as 'an Olympian whinger', the 72-year-old is, worryingly, still struggling to complete the apprenticeship for a job he has known would be his ever since he was in short trousers.
Even in his pampered cocoon, Charles, as a man who strives to do so much that is good, being linked to a cash-for-access controversy bodes badly for his future as king.
l Tom Bower is the author of Rebel Prince, The Power, Passion And Defiance Of Prince Charles.