There are several operating schemes, both mandatory and voluntary. The International Emissions Trading Association provides and overview of the mandatory markets in operation around the world.
1300 854 561 (Advisory)
1300 878 500 (Certificates)
132 Cremorne St,
Cremorne, VIC 3121
Level 1, Block B, 91 Parry Street, Newcastle West, NSW 2302
Level 2, 1-9 Buckingham St
Surry Hills, NSW 2010