Requirements for software systems such as usability, safety, reliability, and security are often called "non-functional" or "system-wide" requirements, in contrast to requirements for domain-specific system functionality such as air traffic control, mission planning, or sales order processing. System-wide requirements differ crucially from functional requirements, in that they are not met by a single component of a system. For example, a geographically distributed system that is not secure cannot be made secure by the addition of a single new module - rather, security requirements need to be addressed in the design of each of the distributed components.
DesignExpert is a tool that helps system developers and stakeholders to analyze organizational needs and requirements in the area of system-wide properties, and to formulate corresponding constraints on the system design and evaluation.
DesignExpert was developed as a cooperative effort between CoGenTex, Drexel University, and Key Software, Inc.