The purpose of this standard is to define normalized taxonomies for system of systems (SoS) to facilitate communications among stakeholders. It also briefly explains what a taxonomy is and how it applies to the SoS to aid in understanding and communication. [Editor??s note: In accordance with the accepted disposition on comment USA-1 and others@ the document has been restructured. Clause 5 now contains two taxonomies Maier@ and Dahmann and Baldwin@ using criteria in Clause 4.3. Other proposed taxonomies@ including related definitions from Clause 3 that do not meet these criteria have been moved intact to annexes.]