This research aims at developing an Integrating Service Design Methodology for business-to-business (B2B) firms to manage the solution life-cycle. Our methodology integrates appropriate modeling tools, e.g., Customer Journey Map, Service Blueprint, Business Process Model and Notation, and Unified Modeling Language, and demonstrates where these tools can be complementary to each other. This research adopts a design science research approach, and applies it to the factory resource asset management solution project and conducts interview with project team members. The contributions in this thesis include that of (i) displaying and delivering similar information through different tools; (ii) achieving efficient communication and reducing information loss within stakeholders (i.e., customer, salesperson, business developer, project manager, and engineer); and (iii) pointing out the differences between the business-to-consumer case and the B2B case in service design.