This thesis states the tasks of the analyst: communicating with commercial customer to establish their requirements; reframing those requirements by negotiation in order that programmers can understand it to write the codes efficiently. Soft System Methodology (SSM) is an effective approach to identify the situation of the problem. In my thesis, I will improve a new business – oriented method that is called Process Improvement for Strategic Objectives (PISO) with SSM to make PISO have more efficiency and more quality. My first scientific contribution is to find the relationship between SSM and information system, explore how to adopt Soft System Methodology into a commercial information system analysis. Then I will do detailed research regarding how to improve PISO method with SSM.