The choice of security level is a decision more likely made by management than by security administrators. That decision depends on answers to the questions "How secure does our company's information need to be?" and "How much do we trust our employees?" Regardless of who makes the decision, it is important that both application developers and security administrators understand the two levels of security supported by z/OS, and the differences between them. The two levels are: UNIX level and z/OS UNIX level. Read the following descriptions to help you decide which level of security is appropriate for your server.