ENThe research aims at the identification of factors influencing mentoring services with a particular emphasis on the country of origin of the mentor and the mentee. The quantitative research was conducted in four Central and Eastern European countries, i.e., Bulgaria, Poland, Latvia and Lithuania and one Southern European country, Italy. The implemented methodology covered Exploratory Factor Analysis (EFA) and reliability analysis, which were performed to identify factors influencing the process of communication in the mentor–mentee relationship. Moreover, to diagnose statistically significant differences between individual countries in terms of factors influencing the effectiveness of communication, the Kruskal–Wallis H Test and the Mann–Whitney U Test, as well as pair-wise comparisons, were used. Factors influencing communication in the mentor–mentee relationship are mentor traits, mentor’s personal background, mentor’s professional background, non-verbal communication channels, communication barriers, written communication channels, online communication, quality of content and the ability of content processing by the mentee. There are differences in the perception of individual factors in the analysed countries. So far, no cross-country comparison has been conducted of factors influencing mentoring services. As a direction for future research, more detailed research can be recommended concerning factors of the mentoring process in such countries as Lithuania, Latvia and Italy by developing separate models (or EFA) for mentors and mentees. Keywords: mentoring services, mentor, mentee, Exploratory Factor Analysis. [From the publication]