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Strategy Bridge

Systems Engineering Glossary

Term Definition

The lowest level of separately identifiable items that cannot be disassembled without destruction or impairment.

Peer Review

An independent evaluation of project deliverables by those with appropriate skills who are not responsible for the effort.


A quantitative measure of physical or functional attribute’s response during the exercise of a process, function, activity, or task.

Performance Index

The measure of effectiveness for each alternative.

Performance Requirement

A description of how well a product or system satisfies a need without regard to how it is accomplished.

Physical Configuration Audit (PCA)

A physical examination of a project’s artifacts to verify that the “as built” Configuration Items conform to the “build to “ documentation that defines them.

Precedence Diagram

A workflow diagram that depicts activity sequences with all predecessor and successor activities.

Preliminary Design

A process to define and architect system performance, components, interfaces, and data to the allocated requirements level.

Preliminary Design Review (PDR)

A review to approve the architecture, decomposition and allocation of requirements, models, and design concepts against system requirements.  The detailed design phase is entered once the preliminary design is approved.  (Typically referred to as the “Design-to-Base-line.”)


Actions that must complete prior to starting an event or progressing to the next phase or activity.

Preventative Maintenance

Actions performed on a regular basis to lesson the likelihood of a system component failure.


Any anomaly determined not to be a failure, but significant enough to warrant recording.


A series of steps or actions to transform inputs into outputs.

Product Baseline

Approved documentation and configuration describing the functional and physical characteristics of a Configuration Item as delivered.

Product Breakdown Structure (PBS)

The hardware and software entities of the program/ project decomposed and expressed in a hierarchical structure.


A defined and planned effort to achieve a common objective across a number of projects.


An activity with a defined beginning and end that consumes resources and produces a product or service.

Proof of Concept

A demonstration that an idea or technology is feasible for use in developing a solution.