Justification asks what "right" the planner has to intervene. It evaluates the planning effort as a whole, often using a moral lens.

The systems approach is based on a paradox (TSA 176): you can't know whether looking at the "whole system" is worthwhile, unless you look at the "whole system". It is a leap in the dark. So far the economic benefits of planning are yet to be determined (TSA, p. 154).

The need for planning varies:
- low (but maybe should be high!): stabilized institutions like banking, research (depends on individual initiatives)
- high: military and space organizations, city governments, ministries.