It has been the appearance of M. Cole's book "Cultural psychology: A once and future discipline" (1996) that made the authors write the given paper. They analyze conceptual notions of cultural-historical psychology: the outer, the inner, interiorization, tools-mediators. They widen the notion of mediator, get over its tool interpretation as an artifact. Their main criticism addressed to M. Cole is underestimation of the role of category of development in cultural-historical psychology.