(28)Pension scheme arrangements are subject to bilateral collateralisation requirements. It is, however, important to avoid excessive burden from those requirements on the expected performance of those schemes and, consequently, on the retirement income of future pensioners. Pension scheme arrangements' liabilities to retirees are denominated in local currencies and their investments must therefore be denominated in the same currency in order to avoid the costs and risks of foreign currency mismatches. It is therefore appropriate to provide that concentration limits do not apply to pension scheme arrangements in the same manner as for other counterparties. However, it is important that adequate risk management procedures are in place to monitor and address potential concentration risks arising from that special regime. The application of these provisions with regard to pension scheme arrangements should be monitored and reviewed in light of market developments.