An anonymous trading system comprises a network of broker nodes each of which perform price matching, deal execution and market distribution. Trader terminals on trading floors are connected to a given broker node via a trading agent node. Credit may be stored for a given trading floor at its trading agent node or at a credit agent node which stores credit limits for a group of trading floors. Where the credit limits of a party to a proposed deal are stored at a credit agent node, the deal execution process is routed through that credit agent node to check for available credit. The system allows institutions to adopt any combination of local and global credit assignments with counterparties with which it wishes to trade.