The G8 summit in Huntsville marked 35 years that leaders of the major industrialized countries have gathered to talk about crucial global issues. Some past summits have kick-started significant initiatives and steered key international policies. Here are some of the most important meetings:

Rambouillet, France, 1975. The G7 had its first meeting when French president Valéry Giscard d'Estaing invited the leaders of the top industrialized countries to talks. There were only six countries at the start – Canada was invited to join for the next year’s session in Puerto Rico. The communiqué said the industrialized democracies were intent on overcoming high unemployment and inflation, and tackling energy problems.

Tokyo, Japan, 1979. A small item in the final communiqué marked a crucial turning point in global environmental policy, said John Kirton, director of the University of Toronto G8 research centre. The leaders pledged to expand alternative energy sources, in order to reduce carbon dioxide and greenhouse gasses in the atmosphere.

Toronto, Canada, 1988. The second summit on Canadian soil (the first was held near Ottawa in 1981) endorsed broad debt relief for African nations, a relatively new concept at the time. The complex formula of debt forgiveness, lengthy repayments and lower interest rates set the stage for further relief in the coming years.

Paris, France, 1989. Just as the summit began, Soviet president Mikhail Gorbachev sent a letter to French president François Mitterrand, suggesting that the Soviet Union was interested in international economic co-operation and wanted to participate in Western institutions. This marked the beginning of a process that eventually brought the Russians into the democratic community, said Andrew Cooper, a distinguished fellow at the Canadian Centre for International Governance Innovation.

Kananaskis, Canada, 2002. Still reeling from the 9/11 terrorist attacks, the world’s leaders focused on issues of security. They approved a plan to spend $20-billion (U.S.) over 10 years to decommission nuclear weapons in Russia and help prevent terrorists from getting their hands on nuclear, biological or chemical materials. Russia became a fully-fledged member of the G8 at this meeting, and the first summit in Russia was set for St. Petersburg in 2006.

Gleneagles, Scotland 2005. With rock stars Bob Geldof and Bono noisily pushing for action, the G8 pledged to double aid to Africa by 2010, a commitment that has not yet been met by every country. The group also promised to make low-cost HIV/AIDS treatments accessible to all who need it by this year – it hasn’t come close to meeting that pledge.

Heiligendamm, Germany, 2007. Brazil, China, India, Mexico and South Africa met with the G8 leaders at this summit, helping to pave the way for the creation of the G20, which is now taking precedence over the smaller group. The final communiqué committed the G8 to participate in the post-Kyoto climate-change process, but there were no firm targets for emission reductions.