Thermo- and photo-induced reactions are discussed from a point of view of a competition between local and global structures. A role of lattice mediation is focused on elastic aspect of the competition: a cavity as a local stress and their interaction. In particular the problem how an interplay between cooperative and competitive role Df the lattice mediation influences a kinetics of a solid state reaction has been addressed. IL is shown that thermal activation is highly cooperative and its energy is a quadratic function of transformed cavities. In a competition with photo-induced transformation. the cooperative activation may cause homogeneous/heterogeneous reaction when induced by weakly/strongly absorbed light.