WThe 13th Extraordinary Convention of the Republican People's Party was held on 29 and 30 January 2005 in order to elect a leader for the Republican People's Party (CHP), a Turkish centre-left political party. Incumbent leader Deniz Baykal was challenged by the Mayor of Şişli, Mustafa Sarıgül for the leadership. The convention was marred by violence between supporters of the two rivals, who had accused each other of corruption and elitism during their speeches. The final result was a victory for Baykal, who won 59.4% of the delegates' votes against Sarıgül's 40.6%.
WThe 117th International Olympic Committee Session was held for the first time in Singapore from 2 to 9 July 2005. Two important decisions were made through voting during the session – namely the selection of the hosting city for the 2012 Summer Olympics, and a review of the 28 sports currently represented in the summer games.
WThe 2005 Commonwealth Heads of Government Meeting was the 19th Meeting of the Heads of Government of the Commonwealth of Nations. It was held in Valletta, Malta, between 25 November and 27 November 2005, and hosted by Prime Minister Lawrence Gonzi.
WAPEC South Korea 2005 was a series of political meetings held around South Korea between the 21 member economies of the Asia-Pacific Economic Cooperation during 2005. Various meetings were held across Vietnam in 2005. Leaders from all the member countries met from 18 to 19 November 2005 in Busan.
WThe 31st G8 summit was held on 6–8 July 2005 at the Gleneagles Hotel in Auchterarder, Scotland and hosted by Prime Minister Tony Blair. The locations of previous G8 summits to have been hosted by the UK include: London ; and Birmingham (1998). It is the first G8 summit to be held in Scotland. A sixth UK summit was held in Lough Erne in 2013; and a seventh UK summit was held in Carbis Bay in 2021.
WThe Le Mans Congress was the twenty-first national congress of the French Socialist Party. It took place from November 18 to 20, 2005.
WThe 2005 NATO Headquarters summit was a NATO summit held in the NATO Headquarters, Brussels, Belgium on 22 February 2005. During this summit, NATO leaders reaffirmed their support for building stability in the Balkans, Afghanistan and Iraq, and commit to strengthening the partnership between NATO and the European Union.
WThe Slovakia Summit 2005 was a summit meeting between United States President George W. Bush and Russian President Vladimir Putin. It took place on February 24, 2005, in Bratislava, Slovakia. This marked the first occasion when a sitting President of the United States visited Slovakia since its independence in 1993. The previous "Bush-Putin summit" had taken place in Slovenia on 16 June 2001.
WThe 4th Summit of the Americas was held at Mar del Plata, about 400 km (250 mi) southeast of Buenos Aires in Argentina, on November 4–5, 2005.
WThe 63rd World Science Fiction Convention (Worldcon) was called Interaction, and was held in Glasgow, Scotland 4–8 August 2005. The event was also the Eurocon. The Venue for the 63rd Worldcon was the SEC Centre with the attached SEC Armadillo and Moat House Hotel. Parties took place at the Hilton Hotel.