Some global governance experts assert that Russia's fallout with the G7 is a belated recognition that smaller international forums comprised of like-minded states are often preferable over larger, more diverse groupings.
Rather than a "G-Zero" world, CFR's Patrick foresees a "G-x world"--one of "multi-multilateralism"--where states adopt an ad hoc approach to collective action, "coalescing in a bewildering array of issue-specific and sometimes transient bodies depending on their situational interests, shared values, and relevant capabilities." For Patrick, the reconstituted G7 serves as one such useful forum among many.
Additional Resources
The University of Toronto's G8 Information Center compiles primary sources from ministerial meetings and summits, analysis, and compliance studies.
The UK Department for International Development compiled the most recent accountability report for the erstwhile G8.
The Overseas Development Institute, a British think tank, critiques the official report's methodology.
Ian Bremmer and Nouriel Roubini argue in this 2011 Foreign Affairs essay that the heyday of the G7 and G20 has passed, saying: "We are now living in a G-Zero world." Bremmer revisited the argument in the New Statesman in 2013.