On 24 August 1991, the Ukrainian Parliament proclaimed full independence, and the Ukrainian population expressed their position on the Act of Independence through a referendum held on December 1, 1991. In this referendum, Ukrainian citizens overwhelmingly expressed their support for independence. Specifically, 84.18% of citizens participated in the vote, with 90.32% of them voting in favour. In order to monitor the attitudes of the population towards state independence, KIIS asks respondents in its surveys what they would do if a referendum on the declaration of independence of Ukraine were held now. The answer options are: to vote for the Act of Independence, to vote against the Act of Independence, or not to participate in the referendum. In the period 2006-2021, 7 waves of the survey were conducted. Each survey wave was carried out on a sample representative of Ukraine's adult population (aged 18 and older), with an average sample size of about 2,000 respondents. For ease of analysis, these seven waves of the survey were combined into one dataset, with a total of 14,158 respondents. The background information includes respondents' socio-demographic profiles (gender, age, education, nationality, occupation, self-assessment of financial situation) and place of residence (oblast, type of settlement). These data enable tracking Ukrainian public opinion on state independence for the period of 15 years, from 2006 to 2021, both among the population as a whole and among its different subpopulations.