The article rethinks the integration of migrants through the lens of constructivist studies of ethnicity. It is done on the basis of the theoretical language developed by the author, which builds upon other constructivist languages. It is pointed out that ethnicity is the organization of differences around categories, membership in which is predominantly inherited. Categories, according to language, are organized in the form of categorizations, classifications, and taxonomies; categories are associated with attributes, which include stereotypes, indicators, norms, characteristics of relationships with other categories, as well as discourses. Together, categories and attributes form the construction of ethnicity, which is a typical object of analysis and description. Individuals constantly evaluate the surrounding phenomena in terms of conformity with the construction of ethnicity, which is why the construction of ethnicity changes. Integration is a change in the construction of ethnicity or re-categorization of individuals in the space of the dichotomy «migrant» - «local» without changing the construction of ethnicity. In the course of integration, «migrant» categories may be re-categorized as «local»; «local» categories may change the attributes associated with them to include attributes previously associated with «migrant» categories; categories and attributes may not change, while re-categorization occurs at the individual level. How exactly integration will take place depends on a variety of factors that characterize the construction of ethnicity and go beyond it. The construction of ethnicity in Russia is a vernacular taxonomy, which implies the existence of a general category (‘Rossijane’, ‘Russkie’), which includes other categories - defined as the «local» ones. Most of the «migrant» categories correspond to identical in name «local» categories. The integration of migrants in Russia thus takes the form of an individual transition from the category of «Tajik migrants» to «local Tajiks». The language created and studied for applicability to the integration of migrants is analyzed for pros and cons and directions for further work are identified.