Develop designs for the service system and service system components.


The term “design” in this practice refers to the definition of the service system’s components and their intended set of relationships; these components will collectively interact in intended ways to achieve actual service delivery.

Service system designs should provide the appropriate content not only for implementation, but also for other aspects of the service system lifecycle such as modification; transition and rollout; maintenance; sustainment; and service delivery. The design documentation provides a reference to support mutual understanding of the design by relevant stakeholders and supports making future changes to the design both during development and in subsequent phases of the lifecycle.

A complete design description is documented in a “design package” that includes a full range of features and parameters including functions, interfaces, operating thresholds, manufacturing and service process characteristics (e.g., which functions are automated versus manually performed), and other parameters. Established design standards (e.g., checklists, templates, process frameworks) form the basis for achieving a high degree of definition and completeness in design documentation.


Examples of other service system design related work products include the following:
  • Descriptions of roles, responsibilities, authorities, accountabilities, and skills of people required to deliver the service
  • Functional use cases describing roles and activities of service participants
  • Designs or templates for manuals, paper forms, training materials, and guides for end users, operators, and administrators

“Designing people” in this context means specifying the skills and skill levels necessary to accomplish needed tasks and can include appropriate staffing levels as well as training needs (if training is necessary to achieve needed skill levels).“Designing consumables” in this context means specifying the consumable properties and characteristics necessary to support service delivery as well as resource utilization estimates for service system operation.

Example Work Products

  1. Service system architecture
  2. Designs of service system components and consumables
  3. Skill descriptions and details of the staffing solution (e.g., allocated from available staff, hired as permanent or temporary staff)
  4. Interface design specifications and control documents
  5. Criteria for design and service system component reuse
  6. Results of make-or-buy analyses


1. Develop a design for the service system.

Service system design typically consists of two broad phases that can overlap in execution: preliminary and detailed design. Preliminary design establishes service system capabilities and the architecture. Detailed design fully defines the structure and capabilities of the service system components.

2. Ensure that the design adheres to allocated functionality and quality attribute requirements.

3. Document the design.

4. Design interfaces for the service system components using established criteria.

The criteria for interfaces frequently reflect critical parameters that should be defined, or at least investigated, to ascertain their applicability. These parameters are often peculiar to a given type of service system and are often associated with quality attribute requirements (e.g., safety, security, durability, mission critical characteristics). Carefully determine which processes should be automated or partially automated and which processes should be performed manually.

5. Evaluate whether the components of the service system should be developed, purchased, or reused based on established criteria.