Abstract: A scenario manager allows users to define document-based choreography and simulate the behavior of a trading partner in a computer system. Rules are utilized to orchestrate the transaction sequence to test the functionalities and performances of the system as a whole and trading partners that participate in a scenario. Each scenario is defined with one or more steps, each of the steps having a condition and/or an action, wherein the condition defines prerequisites for the step to be executed and the action defines what happens if the step is executed. All the steps that have no conditions are executed first, resulting in one or more responses being received from trading partners. Then all steps having conditions that are satisfied in light of any responses received are performed. This is then repeated until no more conditions are satisfied or there are no steps left to perform.