Abstract: In accordance with the principles of the present invention, a graphical user interface for computer trading is provided. A display represents best bid and best ask prices for an execution venue, with one axis representing available prices, and another axis representing time. The display includes a sell area, a bid-ask spread, and a buy area. The boundary of the sell area and the bid-ask spread represents best ask price for the execution venue, and the boundary of the buy area and the bid-ask spread represents best bid price for the execution venue. First indicium on the display represents order executions and second indicium on the display represents orders. The position of the first indicium represents the time and price of the execution, the size represents the size or quantity of the execution, and the colour represents execution type and execution venue.