Increase in emissions outside of the mitigation goal boundary that result as a consequence of activities, such as policies, actions, and projects, implemented to meet the goal. (WRI, 2014) The part of emissions reductions in Annex B countries that may be offset by an increase of the emissions in the non-constrained countries above their baseline levels. This can occur through relocation of energy-intensive production in non-constrained regions; increased consumption of fossil fuels in these regions through decline in the international price of oil and gas triggered by lower demand for these energies; and changes in incomesthus in energy demand) because of better terms of trade. Leakage also refers to GHG-related effects of GHG-emission reduction or CO2-sequestration project activities that occur outside the project boundaries and that are measurable and attributable to the activity. On most occasions, leakage is understood as counteracting the initial activity. Nevertheless, there may be situations where effects attributable to the activity outside the project area lead to GHGemission reductions. These are commonly called spill-over. While (negative) leakage leads to a discount of emission reductions as verified, positive spill-over may not in all cases be accounted for.