to the completion of the clearing, the banks settle payment transactions by debiting the accounts of the depository institutions, while crediting the accounts of depository institutions receiving the payments. The Fedwire Funds Service provides a real-time gross settlement system in which more than 9,500 participants are able to initiate electronic funds transfers that are immediate, final, and irrevocable. Depository institutions that maintain an account with a Reserve Bank are eligible to use the service to send payments directly to, or receive payments from, other participants. Depository institutions can also use a correspondent relationship with a Fedwire participant to make or receive transfers indirectly through the system. Participants generally use Fedwire to handle large-value, time-critical payments, such as payments to settle interbank purchases and sales of federal funds; to purchase, sell, or finance securities transactions; to disburse or repay large loans; and to settle real estate transactions. The Department of the Treasury, other federal agencies, and government-sponsored enterprises also use the Fedwire Funds Service to disburse and collect funds. In 2003, the Reserve Banks processed 123 million Fed-wire payments having a total value of $436.7 trillion. The Fedwire Securities Service provides safekeeping, transfer, and settlement services for securities issued by the Treasury, federal agencies, government-sponsored enterprises, and certain international organizations. The Reserve Banks perform these services as fiscal agents for these entities. Securities are safekept in the form of electronic records of securities held in custody accounts. Securities are transferred according to instructions provided by parties with access to the system. Access to the Fed-wire Securities Service is limited to depository institutions that maintain accounts with a Reserve Bank, and a few other organizations, such as federal agencies, government-sponsored enterprises, and state government treasurer’s offices (which are designated by the U.S. Treasury to hold securities accounts). Other parties, specifically brokers and dealers, typically hold and transfer securities through depository institutions that are Fedwire participants and that provide specialized government securities clearing services. In 2003, the Fedwire Securities Service processed 20.4 million securities transfers with a value of $267.6 trillion. The ACH Network is an electronic payment system, developed jointly by the private sector and the Federal Reserve in the early 1970s as a more efficient alternative to checks. Since then, the ACH has evolved into a nationwide mechanism that processes credit and debit transfers electronically. ACH credit transfers are used to make direct deposit payroll payments and corporate payments to vendors.