This SAE Standard identifies contractor activities for planning and conducting HSI as part of procurement activities on Department of Defense (DoD) system acquisition programs. This standard covers HSI processes throughout system design, development, test, production, use, and disposal. Depending on contract phase, type of the program and/or complexity of the program, tailoring of this standard should be applied. Appendix A lists the requrememts (“shall” statements) in this standard along with unique numbers to facilitate tailoring. In addition, Appendix D provides tailoring guidance to better match requirememts in this standard to the DoD’s Adaptive Acquisition Framework pathways. The scope of this standard includes prime and subcontractor HSI activities; it does not include Government HSI activities, which are covered by DoD and service-level regulations and guidelines. HSI programs should use the latest version of standards and handbooks listed below, unless a particular revision is specifically cited in the contract. Revision A to this SAE Standard improves clarity and reduces redundancies. It also corrects minor omissions, section numbering errors, and grammatical and typographical errors detected in the initial standard that was released in February 2019. No “shall” statements were added or deleted. This revised standard defines, for industry, standard practices required for planning and executing Human Systems Integration (HSI) activities in support of systems acquisition projects. Although primarily developed to address Departement of Defense (DoD) needs, its applicability is not limited to the DoD.