Interest rate risk refers to the profit and loss generated by fluctuations in the forward spreads, along with forward amount mismatches and maturity gaps among transactions in the foreign exchange book. This risk is pertinent to currency swaps; forward outright, futures, and options. To minimize interest rate risk, one sets limits on the total size of mismatches. A common approach is to separate the mismatches, based on their maturity dates, into up to six months and past six months. All the transactions are entered in computerized systems in order to calculate the positions for all the dates of the delivery, gains and losses. Continuous analysis of the interest rate environment is necessary to forecast any changes that may impact on the outstanding gaps.