SAA is a collection of selected software interfaces, 
conventions, and 
protocols that are used as a framework for developing 
consistent, 
integrated applications across the major IBM computing 
environments.

Four major components of this architecture are:
 - Common User Access (CUA) defines conventions for GUI 
look and feel.
 - Common Programming Interface (CPI) provides languages, 
tools, and  APIs that give applications greater portability 
and more consistent user interfaces across multiple 
platforms. 
 - Common Communication Support (CCS) supports existing 
   communications standards, such as LU 6.2. 
 - Common Applications, written by IBM, will serve as 
demonstrations of SAA concepts and make it easy for users 
to migrate between systems.