Question: what are the elements of control and requirements that are essential for establishing control?
Answer: 1) Feedback. Feedback is the backbone of all control systems. ... 
2) Control must be objective. ... 
3) Prompt reporting of deviations. ... 
4) Control should be forward-looking. ... 
5) Flexible controls. ... 
6) Hierarchical suitability. ... 
7) Economical control. ... 
8) Strategic control points.