Scoping is a method of calculating one's carbon footprint.  Carbon accounting (also known as personal disclosure or carbon footprinting) involves counting all the CO2-e that you or your company has released, or is responsible for releasing. 

Scope 1 refers to onsite emissions (e.g. natural gas usage), Scope 2 is for off-site direct emissions (e.g. electricity usage), and Scope 3 accounts for all other indirect emissions (e.g. employee travel or off-site meetings). GOs provide the consumer a way to manage their Scope 2 emissions.  For more information on scoping visit the website of the Green House Gas Protocol.