美國國防部對於武器採購，在採購人員方面必須依循採購法有關契約官Contracting Officer的法條規定，在採購部門的相關程序書中會制定Acquisition Guidebook，例如國防部就會制定Defense Acquisition Guidebook (DAG)，DAG會參考諸如軍事採購法、聯邦採購政策局法、締約競爭法、購買美國貨法、小型企業法、聯邦獲得精實化法、聯邦獲得革新法、採購法 (FAR)、國防部採購法增補(DFARS)、國防部國防部5000系列文件（DoD’s 5000 Documents）。DAG猶如一份總合的採購人員經典參考書，在該書中就有敘述Standards與Capability Maturity Model的差異，以避免採購人員在採購文件中用錯以致增加履約困擾：

The major distinction between standards and capability maturity models lies in their purpose. Standards provide recommended processes to apply within an organization, describe expected tasks and outcomes, and describe how the processes and tasks integrate to provide required inputs and outputs. Standards are meant to provide an organization with a set of processes that, if done by qualified persons using appropriate tools and methods, will provide a capability to do effective and efficient engineering of systems. Capability maturity models, on the other hand, are for process improvement. Capability maturity models are used to assess, from an organizational perspective, how well the standard processes are being performed. Both capability maturity models and standard processes are useful to an organization, but the role for each should be kept in perspective. To actually accomplish systems engineering, an organization may use any or all of these standards to define and tailor how they will apply systems engineering to their programs. This tailored approach should be coordinated with the systems engineering technical authority for the program. The INCOSE SE Handbook, "A Guide for System Life Cycle Processes and Activities," provides guidance for organizations within the ISO/IEC 15288 framework.