4. Who

Who is concerned by the development and management of "complex systems"? A priori, the field is very broad. It includes all engineers. The range of responsibilities covered is therefore very broad. The only important criterion is that the engineer has to design, build, operate or deconstruct a set of interacting elements (people and/or machines) assembled to achieve a goal, i.e. a system. In other words, a system, from the CEO down to the front-line technician.

In other words, the people concerned are those who have to solve difficult or apparently simple problems.