Faced with a financial and economic crisis, G20 leaders pledged at the 2009 Pittsburgh summit to undertake massive reforms in the banking sector in order to prevent a repeat of the meltdown.
Two years later, the heads of the world's most powerful economies meet again this week, at the G20 summit in the French resort of Cannes.
Here is a recap of the three key areas in which regulations were to have been tightened up and of the status of the reforms:
A big chunk of banking reforms fall under the so-called new "Basel III" rules, aimed at making banks more resilient to future shocks by bolstering their capital.
At Pittsburgh, leaders called for stricter rules, to be developed by 2010 and implemented by the end of 2012.
The rules require banks to raise their high-quality, easily accessible, core common equity to 7.0 percent of total assets from the current 2.0 percent.
In addition, regulators have asked 28 of the world's biggest banks to set aside 1.0 to 2.5 percentage points more in Tier 1 capital.
If these large banks decide to increase their size substantially, they would be required to set aside a further 1.0 percentage point.
The list of these 28 big banks should be published during the Cannes summit and the new standards should enter progressively into force from 2013 to early 2019.
But they have been criticised by some bankers as too costly. JP Morgan Chase chief executive Jamie Dimon called the new rules "anti-American" in an interview with Financial Times.
"I'm very close to thinking the United States shouldn't be in Basel anymore," Dimon said.
During the 2009 summit, heads of state said that "excessive" compensation for executives in the banking sector should end as it encourages risk-taking, which accentuated the financial crisis.
The G20 opposed guaranteed multi-year bonuses, urged greater transparency and called on the G20's Financial Stability Board to propose new measures by March 2010.
New principles included axing bonuses when companies perform badly and abolishing "golden parachute" payouts amid mounting public anger over bonuses paid to executives at failing firms.
Regulators said there should be "full implementation" of these principles before the the 2009 bonus round came around.
In March 2010, regulators assessed that financial institutions were still not doing enough to factor in risks when drawing up bonuses.
But by October 2011, regulators said 20 major international banks were found to have made progress and their compensation practices "appear, on average, to be broadly consistent with nearly all elements of the Principles and Standards."
In 2009, G20 leaders asked for reforms of the trillion-dollar derivatives markets that were blamed for helping trigger the global financial crisis.
They have sought specific reforms to be implemented in the so-called OTC (over-the-counter) derivatives markets by end 2012.
In October 2010, global regulators recommended 21 reforms to derivative trading, calling on authorities to increase standardisation in the market, with a central clearing system to ensure orderly settlement of trades.
They also recommended reporting to trade repositories to give authorities a global view of the markets.
But progress has been delayed by debt turmoil in the eurozone.
On October 4, 2011, the European Union finally sealed a deal on regulating OTC derivative trades in the bloc.
New regulations require clearing houses that handle more than five percent of the market in a euro-denominated financial product to be based in the eurozone.
On October 11, regulators urged countries to "aggressively push forward" reforms, warning that few countries "have the legislation or regulations in place to provide the framework for operationalising the commitments."
Britain's financial centre controls three-quarters of the derivatives trade across Europe and half of the trade worldwide.