The article aims at the explanation of some distributional peculiarities of two high unrounded vowels [i] and [È] in Russian. More generally, it looks at some phonotactic constraints of Russian vowels which are directly related to a broader topic of palatalization and vowel reduction in this language. Although the discussion in this paper concerns only a tiny section of Russian phonology, which is the distribution of high unrounded vowels, it is necessary to introduce several facts from Russian phonology, such as palatalization, velarization, stress and vowel reduction. They, at first sight, may look pretty much irrelevant to the main topic of the paper but, as it will become evident, are closely related and actually indispensable to the understanding of vowel distribution including the two high unrounded vowels in Russian.