What has been said thus far relates primarily to correspondent relationships between banks situated in the same country. The international relationship of banks which act as correspondents for one another is very similar, but is necessarily more complex and involves more responsibilities. In such international relationships, the most important functions to be performed are those of mutually acting as agents for one another in the opening of credits, thus facilitating the movement of goods from country to country, while the proceeds of collection will be carried on open account, or remitted, according as circumstances dictate. These are what are technically known as foreign-exchange transactions, and are more fully dealt with elsewhere. It is worth while to mention them at this point because they are illustrative of interbank relationships in the largest sense, and because they are precisely on a parity with domestic interbank relationships. The difference lies in the fact that in international trade there is more call for the actual advancing of funds, while differences in currency units and values involve a greater degree of responsibility in holding such funds. But it should be borne in mind that what is called "foreign exchange" as conducted at the present time is a special phase of interbank business, in which a bank in one country acts as collecting agent for a bank in another, and frequently adds to this function that of rediscounting or purchasing paper or assuming the responsibility for credit at the request of its correspondent bank.