This paper describes a new strategic information system planning methodology, called ISISP (Integrated Strategic Information System Planning), which combines both topdown and bottom-up methodologies for strategic information system planning. In ISISP, portfolio derived from CRUD matrix will union with portfolio derived from SWOT/strategic themes which results in three sets of applications, namely the existing non-core applications, the core applications and the future applications. Then application transformation is applied to both core and non core application groups. For the future application group, each application will be mapped onto the existing CRUD matrix resulting in a new CRUD matrix, called ICRUD, which represents the information architecture that bridges the existing applications to the future strategically derived mission critical applications. The ISISP methodology therefore facilitates the actual implementations since all application boundaries will be derivable for the ICRUD matrix. Also, the business areas will be focused and realistic. The resultant application portfolio would be more suitable for creating IT-enabled enterprise since both existing and future strategic applications are taken care for.