This article seeks to analyse the statistical treatment of ethnic minorities in three comparable Central Asian states, viz. Kyrgyzstan, Tajikistan, and Uzbekistan ― through a specific region divided between the three countries: the Fergana Valley. The author’s assumption is that ethnic groups which used to have a legally equal status under the Soviet regime are now subject to differential treatment. The author notably shows that depending on each post-Soviet state ethnic categories do not have the same meaning. His detailed analysis of the censuses, compared with other statistical sources and cross-checked in the field, helps him to understand how each country addresses and treats its ethnic minorities. The census of 1999 in Kyrgyzstan sheds light on the rapid acquisition by the country’s Uzbek population of the consciousness of forming a critical mass population, and partially explains the promotion of language as the key demand of Uzbek leaders. The changes introduced in the 2000 census’ procedures in Tajikistan highlight the Rahmon administration’s intention of limiting the Uzbek representation, and of dividing the Uzbek group into new entities. As to Uzbekistan, the postponement of the first population census reflects the wariness of the authorities to address the ethnic question (evoked through the local official echo to the publication, in 2002, of an iconoclastic Ethnic Atlas of Uzbekistan). As a conclusion, O. Ferrando also reminds that figures do not explain the attitude or strategy of respondents, and insists on the fact that only a bottom-up approach of ethnic groups provides information on the appropriation or subversion of the imposed categories. His study, in all, casts light on the decisive role of Central Asian states in these manipulations since the end of the Soviet period, and provides us with an interesting example of the necessity for social scientists specialising in the region to combine a variety of sources and approaches for managing to define the objects of their research.