The summit's priorities included evaluating the progress of financial reform, developing sustainable stimulus measures,[1] debating global bank tax,[2] and promoting open markets.

Prior to the summit, Canadian Prime Minister Stephen Harper announced that the theme would be "recovery and new beginnings," referring to an anticipated economic stimulus from the impact of the ongoing world recession.

Organizers later deemed the town insufficient to provide hospitality for the large number of G20 delegates and journalists, favouring Toronto as the host location.

[13] Some invitees expressed criticism of Israel's Gaza strip blockade and of the nuclear programs of North Korea and the United States raised issues of corruption and security in Afghanistan.

[17] According to an early estimate by The Globe and Mail, 25,000 uniformed police officers, 1,000 security guards from Commissionaires Great Lakes, and several Canadian military forces were to be deployed during the summit.

[18] The North American Aerospace Defense Command (NORAD) conducted Amalgam Virgo exercises on May 6 and 7 across the Greater Toronto Area using CF-18 Hornet jets, CH-124 Sea Kings, and CH-146 Griffon helicopters at low altitudes.

[25] The Toronto Police Service installed 77 additional closed-circuit television security cameras in the area and purchased four Long Range Acoustic Devices which were to be in use exclusively during the summit.

[52] The pavilion included three life-sized government-funded displays: Cityscape, which showcased successful Canadian businesses and innovation; The Bridge, which included information kiosks for media personnel as well as large high-definition screens that televised the 2010 FIFA World Cup games; and Northern Ontario Oasis, an artificial lakefront based on Muskoka region's cottage country.

[53][54] The Northern Ontario Oasis included donated canoes, a shoreline with deck chairs for journalists to cool off, and a mobile phone recharging station.

[60] British prime minister David Cameron arrived on June 25, following a short visit in Halifax to celebrate the centennial of the Canadian Forces Maritime Command.

[61] The Organisation for Economic Co-operation and Development and the International Labour Organization, as well as Ethiopia, Malawi, Nigeria, and Vietnam made their first G20 summit appearances in Toronto.

[4] Recently designated heads of government, namely Cameron and Japanese prime minister Naoto Kan, made the G8 and G20 summits their first international conferences.

[62] After the G8 summit in Huntsville, Ontario ended, Cameron, whose aircraft was grounded due to weather conditions, shared transportation to Toronto in Marine One with US President, Barack Obama.

[98] Nearby hospitals, shopping centres, and hotels were put in lockdown mode while public transit services were diverted from downtown to other locations.

[105] Ultimately, a constable would be convicted of assaulting a protestor and a superintendent of unlawful arrest and discreditable conduct for ordering the "kettling" incidents; both received notional punishments and kept their police jobs.

[106][107] In October, 2020, more than a decade after the summit, the Toronto police conceded that "there were times when matters were not addressed in the way they should have been and many hundreds of members of the public were detained or arrested when they should not have been and were held in detention in conditions that were unacceptable."

This was partially due to most countries' entering recovery mode from the global economic recession after the past G20 summits; thus, the likelihood of new issues being raised was minimal.

[citation needed] During the working dinner for G20 leaders on the evening of June 26, South African president [Jacob Zuma] promoted more partnership between the international community and Africa for the development in the continent.

It also recommended that emerging economies such as China, which has largely benefited from trade surpluses, rely less on developed nations and increase their own spending in order to promote domestic demand.

Members of Parliament Olivia Chow and Mark Holland labelled the initially claimed budget of $1.1-billion for hosting the summits as "obscene" and "insane" while others argued that the money could have been used for long-pending municipal projects in Canada,[119][120] such as Transit City.

[119] However, the Canadian Parliamentary Budget Officer, Kevin Page, stated in his official report on the costs of the Huntsville and Toronto gatherings that other countries had not been as open about the full price for the similar meetings held there and that the $18 million figure for the Pittsburgh summit was merely for overtime pay for local police and the cost of law enforcement brought from other regions.

"[123] The creation of the $23-million international media centre, which included the $1.9 million Experience Canada pavilion and $57,000 artificial lake, at the Exhibition Place was widely opposed and criticized by politicians as "a waste of taxpayers' money.

[125] In a debate in the House of Commons, member Mark Holland said, "Instead of hosting world leaders, maybe the government should consider party planning for Lady Gaga.

Transport minister John Baird defended the artificial lake, saying that the summits gave a "chance to showcase the very best that [Canada] has to offer."

Foreign affairs minister Lawrence Cannon said it was "normal practice" for a country to showcase its attributes while hosting world events.

[131] According to Member of Parliament John McCallum, "Stephen Harper made a huge mistake in holding this summit in downtown Toronto."

The alert, which was expected to expire on the last day of the summit, stated that "Even demonstrations that are meant to be peaceful can become violent and unpredictable."

A reporter of the British Broadcasting Corporation (BBC) made positive remarks about Canada's economy, saying "The Canadians, it seems, have answers for even the toughest puzzles and they are keen to share their strategies with the rest of the world.

The Times of India and The Hindu commented on impacts on city life in Toronto due to the G20 summit and the "unprecedented" security measures taken in Canada.