The author examines several provisions of using library’s domain name to personalize library and information services within the policy of library brand development and promotion. The library’s presence in the digital environment cannot be achieved without efficient branding strategy. It is vitally important to choose and use the “right” domain name to make users to identify the library’s website, to ingrain their positive associations – that is the main aim of registered service mark as the domain for the library’s website in the World Wide Web. The author focuses on personalization function of the library’s domain name similar to that of the service mark, The domain name is cited in advertising, used in official email addresses and, as a result, the users associate it with the library on the whole and its brand, in particular. Inclusion of the service mark as a verbal image into the domain name is an essential element of developing concerted strategy of individualization in the digital space. Similarities and differences in the functions of domain names and service marks as instruments of personalization in library and information activities are specified. The main accent is made on legal characteristics of the library’s service mark and domain name. The author examines the possibility to personalize library services in the digital space with domain name, as well as she emphasizes the role of Russian-language domain in expanding online resources usership.