  A microscopic model of indirect exchange interaction between transition metal
impurities in dilute magnetic semiconductors (DMS) is proposed. The
hybridization of the impurity d-electrons with the heavy hole band states is
largely responsible for the transfer of electrons between the impurities,
whereas Hund rule for the electron occupation of the impurity d-shells makes
the transfer spin selective. The model is applied to such systems as $n-$type
GaN:Mn and $p-$type (Ga,Mn)As, $p-$type (Ga,Mn)P. In $n-$type DMS with
Mn$^{2+/3+}$ impurities the exchange mechanisms is rather close to the
kinematic exchange proposed by Zener for mixed-valence Mn ions. In $p-$type DMS
ferromagnetism is governed by the kinematic mechanism involving the kinetic
energy gain of heavy hole carriers caused by their hybridization with 3d
electrons of Mn$^{2+}$ impurities. Using the molecular field approximation the
Curie temperatures $T_C$ are calculated for several systems as functions of the
impurity and hole concentrations. Comparison with the available experimental
data shows a good agreement.
