CATWOE

To define the transformation:
"A system for C owned by O with resources R to do X by Y under constraints E"

• C the customer "for C"
• A the actors or users "done by actor A"
• T the transformation "do X by Y"
• W the Weltanschauung, belief contained in the definition e.g. such a system is possible.
• O the owner "owned by O"
• E the environmental constraints "under constraints E"