The operating system bears a tremendous burden in achieving security. Because the operating system controls the resources (e.g. memory, processing time, devices) of the computer, it has the power to prevent unauthorized access to these resources and information flowing through them. Conversely, if the operating system fails to prevent or limit the damage resulting from unauthorized access, disaster can result. With the recent NSA evaluation of INTEGRITY to the Common Criteria SKPP standard, there now exists, for the first time in history, an operating system that can be trusted to protect corporate intellectual property, financial records, private customer information, national secrets, and critical control systems such as the power grid. This white paper will discuss the SKPP, now the gold standard for operating system security.