The article is devoted to the analysis of the concept of apparent time used by modern sociolinguistics to identify the social features of the use of language by various socio-demographic groups. There are a number of problems that can be solved by using this empirical method. The fi rst problem is the “constraints”: which language changes are possible and which are not. Historical data can only show what changes have already occurred, but not what changes are possible/impossible. The second is the problem of “embedding”: how a language changes reach all (or almost all) the community members. The third problem is “assessment”: how community members react to language changes and what impact their assessments have on the course or nature of changes. The fourth is a “transitional” problem: how does the language change from one state at the moment A to another state at the moment B. Finally, the fi fth problem is “actualization”: why there is a change in a particular language, when and where it occurs. The founders of the method, Weinreich, Labov and Herzog, argued that these important problems can only be solved by observing the change of language as it arises and from different social points of view, including a wide range of ages, social statuses and places of residence. The diffi culties of applying this concept are considered: there are few comparable real-time data on earlier periods; methods of early work and socio-demographic characteristics do not correspond to modern research needs. The ways to overcome these diffi culties are proposed: research should be of a longitudinal nature with the unifi cation of the methodology for obtaining empirical data.