According to the EU ETS Directive (Art. 1), the objective of the ETS is to “promote GHG reductions in a cost-effective and economically efficient manner”. Hence, the over-arching objective is cost-effective achievement of a politically given target. By some, including most conventional economists this is construed as a call for the lowest possible EU allowance price, for example allowing the use of as many offsets as possible – provided they reflect real reductions to reach a given objective.