Dealing with carbon emissions comes at a price, obviously. As often, the trigger came from the regulatory authorities who encouraged big GHG emitters to curb their output. To that extend, authorities had the choice between raising dedicated taxes related to the GHG volume emitted, and the free granting of permitted emissions volumes system, also called 'grandfathering' or 'cap and trade'.

This latter system, adopted by the EU with its European Union Emissions Trading Scheme, has  lead to the creation of a commodity-like carbon trading market where European Union Allowances (EUA)can be exchanged.

There are two market places where EUA's are traded: ECX (only Futures) and Bluenext (Spot and futures).

For companies resorting to this scheme, one of the typical strategy is to sell spot the received allowances and buy futures contracts according to their expected real needs, hence generating cash surpluses on the short term.

This apparently simple strategy however has some consequences:

- The market moves strongly in one direction at each allowance period renewal and expiration date.

- On the tax side, it is usually not possible to clear the sale with the forward purchase, meaning that corporates are taxed on the profit made through spot selling their allowances, although on the whole it constitutes a virtual profit to be offset by the forward purchase.

As climate change eventually is a global concern, the Kyoto Protocol has come up with a inventive scheme aiming at creating win-win situations, namely the Clean Development Mechanism (CDM).

The basic idea is for Annex I countries companies for which the cost of curbing their emissions is too high (or simply not realistic) to invest in projects targeting GHG emissions reductions hosted in Non-Annex I countries.

This too has lead to the creation of an exchange market where primary and secondary Certified Emission Reductions (CERs) securities are traded.

For those companies not resorting to any Cap and Trade scheme, there is also the possibility to enter into a one to one offset transaction. The idea here is to directly participate to the financing of Carbon emission lean projects in developing countries, in order to compensate own emissions. Although no official obligations or market is here at stake, a company may chose to enter in such a deal for pure governance reasons and/or competitive positioning through communication.