INCOSE Systems Engineering Handbook, 5th Edition

PREFACE

The objective of the International Council on Systems Engineering (INCOSE) Systems Engineering Handbook (SEH) is to describe key Systems Engineering (SE) process activities. The intended audience is the SE practitioner. When the term “SE practitioner” is used in this handbook, it includes the new SE practitioner, a product engineer, an engineer in another discipline who needs to perform SE, or an experienced SE practitioner who needs a convenient reference.

The descriptions in this handbook show what each SE process activity entails, in the context of designing for required performance and life cycle considerations. On some projects, a given activity may be performed very informally; on other projects, it may be performed very formally, with interim products under formal configuration control. This document is not intended to advocate any level of formality as necessary or appropriate in all situations. The appropriate degree of formality in the execution of any SE process activity is determined by the following:

The need for communication of what is being done (across members of a project team, across organizations, or over time to support future activities)

The level of uncertainty

The degree of complexity

The consequences to human welfare

On smaller projects, where the span of required communications is small (few people and short project life cycle) and the cost of rework is low, SE activities can be conducted very informally and thus at low cost. On larger projects, ...