Mixed gender agreement has been widely discussed in Russian linguistics. Most work on this topic considers hybrid nouns - animate nouns that can refer to both male and female individuals and can bear the agreement patterns reflecting either the initial gender value of these nouns or the gender value of their context referent (Wechsler and Zlati ́c 2003, Pereltsvaig 2006, Matushansky 2013, Pesetsky 2013, Rappaport 2013, Landau 2015). However, agreement with other elements that can refer to both male and female individuals, such as non-gendered pronouns, has not received much theoretical attention. This paper analyses mixed agreement in constructions involving the interrogative/relative pronoun kto ‘who’. Although in most cases, kto ‘who’ triggers default masculine agreement, sometimes the agreement target reflects the initial gender of the referent of the pronoun.