By Andrew Walker
BBC News, Pittsburgh
US President Obama said the G20 took "bold and concerted action"
The G20's leaders have moved on a little.
When they last met in London in April they were still on the brink, wondering whether the world might be facing an economic depression.
So they threw everything at the problem. In the Pittsburgh communique they concluded "it worked".
They are not denying that there is more work to do to make the current stirrings of recovery durable. But it does mean they can look a little further into the future.
One leading preoccupation now is preventing future financial crises. To do that, they plan an overhaul of financial regulation, with the aim of discouraging the high levels of lending to borrowers who were liable to default, that was a central feature of the crisis.
Bankers' bonuses are an important element in the reforms. With this issue there's a lot of politics.
WHAT IS THE G20?
Set up after the Asian financial crisis in 1999 as a forum for finance ministers and central bankers
First G20 leaders summit in 2008 to discuss response to economic crisis
Members are: Argentina, Australia, Brazil, Canada, China, EU, France, Germany, India, Indonesia, Italy, Japan, Mexico, Russia, Saudi Arabia, South Africa, South Korea, Turkey, UK, USA
Joined by Spain, Netherlands, International Monetary Fund and World Trade Organisation
Leaders know that many voters are appalled by the amount that some bankers receive, and some want to show they are responsive to those concerns. And if you think the kind of inequality that financial sector pay produces is unethical, you would want politicians to respond.
But there is another, more pragmatic reason for the G20 to take on bankers' pay. It can give them an incentive to take risks, to make a quick but unsustainable profit and then cash in a bonus.
So the G20 plan rules to make that harder to do. They want bonuses to be linked to long-term performance and to enable banks to claw them back in some cases.
There is no plan for general caps on the amount banks can pay out, something that some European governments wanted. The one exception is that the G20 proposals would limit a bank's bonus payments if paying out too much would endanger its financial soundness.
Will it work? There are plenty of people in finance who are ingenious enough to find ways round many regulations. With bonus rules the motive for making the effort is obvious.
Another key area is the amount banks have to keep in reserve to absorb losses - their capital. The key element is money from shareholders or profits not paid out as dividends to shareholders.
The G20 want to increase the size of the financial cushion that banks have to maintain.
It might make a difference, but it will depend on how much extra capital they have to hold, and that has not been agreed.
Some elements of this plan are likely to be very complex. For example, making these capital requirements more onerous in boom times is a good idea in theory. Why not make banks put a lot more aside in the good times, so they can better weather the storms?
The problem is that it will be difficult to spell out in practical terms.
There's another theme in the communique that could help prevent crises - global economic imbalances. They were partly responsible for the crisis.
Chinese consumers saved and the government built up foreign currency reserves. Much of this money was lent to the US and it enabled American consumers to borrow easily. They did and many got into financial difficulty.
The G20 communique does have an outline plan for some countries to stimulate more spending and less saving. There are no names, but China is the obvious candidate.
There is, however, no real enforcement mechanism beyond an unfavourable assessment from the International Monetary Fund.
The G20's plans do address some real problems that contributed to the crisis.
But a very complex financial world is fiendishly difficult to regulate effectively.
If the G20 countries do all they say they will, it might reduce the risks to the banking system. But it is just not realistic to expect to banish crises for good.