  Some physical implications involved in a new concept, termed the "quantum
protectorate" (QP), are developed and discussed. This is done by considering
the idea of quantum protectorate in the context of quantum theory of magnetism.
It is suggested that the difficulties in the formulation of quantum theory of
magnetism at the microscopic level, that are related to the choice of relevant
models, can be understood better in the light of the QP concept . We argue that
the difficulties in the formulation of adequate microscopic models of electron
and magnetic properties of materials are intimately related to dual, itinerant
and localized behaviour of electrons. We formulate a criterion of what basic
picture describes best this dual behaviour. The main suggestion is that
quasi-particle excitation spectra might provide distinctive signatures and good
criteria for the appropriate choice of the relevant model.
