Dynamic price improvement

A electronic trading system for the exchange of financial instruments, said system comprising at least one processor, the processor or processors of the system being configured to:

• receive and store orders to buy and to sell financial instruments as submitted by traders, and substantially as orders are received, to execute trades between matching buy and sell orders, stored buy and sell orders having order matching priority orderings relative to each other reflecting at least one attribute of the order in addition to or instead of price, the order matching priority used by the electronic trading system to determine order matching priority among orders for matching for execution;
• receive a dynamic price improvement order, being an order to buy or sell an identified a financial instrument traded on the electronic trading system, whose order matching priority for execution against contra orders is maintained by the electronic trading system at least in part relative to earlier-submitted orders on the same side of the market by adjusting a price associated with the dynamic price improvement order;
• receive orders contra to the dynamic price improvement order, and match the contra order to the stored orders on the same side of the market as the dynamic price improvement order substantially as the contra orders are received, the dynamic price improvement order being matched to the contra orders with the order matching priority relative to other orders as maintained by the electronic trading system, and
• execute transactions substantially as orders and contra orders are matched.