Abstract: Medium-size system integration or IT Solution Company’s solution development project has limitation as like human resource limitation, budget limitation and expert limitation. Especially it is hard to maintain many IT experts for medium-size and small-size system integration or IT Solution Company. Thus in order to efficiently and beneficially complete projects, medium-size and small-size system integration or IT Solution Company should have appropriate solution development methodology. Solution development projects for medium-size and small-size system integration or IT Solution Company are usually shot-term and small budget so that they need slim and light-weight solution development methodology. But usual medium-size and small-size system integration or IT Solution Company do not have their own appropriate solution development methodology. Thus, if those kinds of solution development methodologies are applied to solution development projects for medium-size and small-size system integration or IT solution company without some modifications, shortage of human resources, incompleteness of solution and deliverables could arouse. Especially unnecessary paper works (deliverables and documentations) to both of projects teams and client’s wastes project resources and time. We analyze previous solution development methodologies and derive mandatory deliverables and optional deliverables. Before deriving them, we newly define procedures and tasks for each project stages which are necessary to projects team and clients, from client and expert of interviews. Our proposed solution development methodology can easily leverage the development overhead of short-term projects. Optional deliverables can be omitted by the contraction between project team and client.