Boris Johnson has fewer powers than his New York counterpart
When newly-minted London Mayor Boris Johnson and New York Mayor Michael Bloomberg sit down to swap notes on the behemoth task of running great cities, each man will no doubt cast a jealous eye at some point over the other's role.
Mr Johnson would no doubt like to take a bite out of the Big Apple's £30bn annual budget, compared with £11.3bn at London's City Hall.
New York's money comes in large part from the mayor's unrestrained ability to raise revenue through taxation.
For his part, Mr Bloomberg may covet the Conservative Party London mayor's power to implement key policies - such as congestion charging - without having to jump through legislative hoops.
Mr Bloomberg's plan for a congestion charge in Manhattan was rejected by New York state lawmakers in April 2008, costing the city's transport system a much-needed annual cash injection.
Indeed, both men might come away from their Friday meeting wondering if the mayoral grass is greener on the other side of the Atlantic.
In a straight contest over power and revenue, New York's billionaire businessman and two-term mayor wins hands down.
He was first elected mayor in 2001 as a Republican despite being a long-time Democratic Party supporter. After winning re-election in 2005, he left the Republican Party and changed his political status to unaffiliated.
His role, in a post which has been directly elected by New Yorkers since 1834, puts him in charge of all city services such as rubbish collection, social services, policing, fire and schools in the city of eight million people.
Property taxes - the council tax equivalent - is set by city council led by the mayor, as is the real estate tax (similar to stamp duty in the UK).
The monies raised stay within the city coffers to pay for local services. The city of New York employs just shy of 370,000 people, compared with 700 directly employed by the Greater London Authority and the London Assembly.
In London, with a population of 7.5 million, the mayor's office is reliant on policies set at Westminster for the lion's share of its budget and the ability to raise revenue is limited to the headline-grabbing congestion charge and work-place parking charges.
The very job description of London's mayor, in place since former Prime Minister Tony Blair recreated the role after Labour won the 1997 general election, has a ceremonial tone.
The mayor's role is: "To work with other London bodies to promote economic development and wealth creation, social development, and the improvement of the environment."
Is the mayoral grass greener on the other side of the Atlantic?
Compare that to the gravitas afforded to Mr Bloomberg's job: "The Mayor of New York city is the head of the executive branch of the government of New York city."
Yet Mr Bloomberg has been denied the high-profile victories that Mr Johnson's predecessor, Ken Livingstone, enjoyed during his eight years as London's mayor.
On top of the congestion charge rebuke, Mr Bloomberg's power and cash flow could not convince legislators to approve a stadium in Manhattan which might have boosted New York's chances of landing the 2012 Olympics; games that are now high on Mr Johnson's agenda.
Mr Bloomberg inherited a £3bn deficit from former mayor Rudy Giuliani amid the aftermath of the 11 September attacks and was forced to raise taxes upon his election in 2001.
London's economic boom has been longer and stronger.
Even Mr Bloomberg posited last year that he worried that London was on the verge of overtaking New York as the world's capital of finance, amid a climate of regulatory pressure that analysts said was driving business out.
Although he has since stressed New York's continuing strengths - and offered to share his top tips for success with Mr Johnson - it is expected that Wall Street will suffer more than the City of London when it comes to financial sector job losses amid the credit crunch.
What London's mayor might lack in power he perhaps gains in influence, given his ability to appoint key board members to the agencies that keep the city running, including the Metropolitan Police Authority and Transport for London.
He is also armed with strong planning approval and veto powers that hand him a direct say over which projects are built and what physical shape the city will take over the next four years.
For Mr Johnson, the reality that his powers are fewer and pockets not quite as deep as the New York mayor could also help bring more focus to the job at hand.
With a £450m London Development Agency budget within his grasp, he should be able to prioritise his campaign promises of improved public safety, better public transport, improved use of the Thames for commuters, tackling youth crime and making key changes to the London Plan to limit development of back garden space.
The London mayor also has the responsibility to set the agenda and the budget for affordable housing in the city - which in turn produced his promise to create 50,000 new units by the tight deadline of 2011.
On a note of self-interest, Mr Johnson can take some comfort in the fact that his job pays more than his American counterpart, earning him £137,000 annually, compared to £98,000 for the job in New York, although the job stateside comes with the plush Gracie Mansion in Uptown Manhattan.
Of course, with a personal fortune estimated to be in excess of £5bn, Mr Bloomberg opts for a salary of just $1 a year and pays all his own expenses.