Specialty Engineering (glossary)
(1) A component of Systems Engineering that complements the technical activities required to deliver a project. It typically deals with engineering that affects the performance, safety, usability, cost certainty, constructability, deliverability and lifecycle of the product outside of the normal functional aspects of engineering. (INCOSE 2015)
(2) The collection of those narrow disciplines that are needed to engineer a complete system. (Elowitz 2006)
(1) INCOSE. 2015. INCOSE Infrastructure Working Group. Available at: INCOSE https://www.incose.org/docs/default-source/Working-Groups/infrastructure-wg-documents/005-specialty-engineering-pamphlet.pdf?sfvrsn=9c2c82c6_6.
(2) Elowitz, M. 2006. "Specialty Engineering as an Element of Systems Engineering." Presentation to Enchantment Chapter, INCOSE. Albequerque, NM, USA, 9 August 2006.
The definition of "narrow disciplines" is context dependent, and can include traditional domain disciplines (electrical engineering, mechanical engineering, etc.) as well as integrative disciplines (human systems engineering, safety engineering, etc.).