As of June 2013, there are 192 parties to the Kyoto Protocol to the United Nations Framework Convention on Climate Change, which aims to combat global warming.
[1][2] Canada renounced the protocol effective 15 December 2012 and ceased to be a member from that date.
Ratification means that a state is legally bound by the provisions of the treaty.
For Annex I parties (e.g. a developed state or one with an 'economy in transition') this means that it has agreed to cap emissions in accordance with the Protocol.
With Russia's ratification the "55 percent of 1990 carbon dioxide emissions of the Parties included in Annex I" clause was satisfied and the treaty was brought into force, effective 16 February 2005.