Methods and systems for computer-based incremental trading are provided. Owners of the top price/time priority orders are able to trade between each other multiple numbers of times prior to the expiration of a workup period, at which time the workup orders of all the users participating in the workup are matched. The workup period is private between the owners of the top price/time priority orders and the orders are allowed to be modified multiple times. When the workup period ends, orders are matched according to the original price/time priority.