The aim of this paper is to verify the applicability of the toolkit developed to assess and compare the internationalisation of universities in terms of its effectiveness and quality. For this purpose, a survey in the form of a questionnaire (one of the proposed tools) was conducted for a group of 57 universities from Poland, Czechia, Ukraine, and the UK. The toolkit made it possible to rank universities in terms of the quality and effectiveness of internationalisation, and allowed for an individual assessment of the level of internationalisation. Results show there are differences in the level of effectiveness and quality of internationalisation between the four countries surveyed. In the UK and Ukraine, there is significant difference in internationalisation effectiveness ratings for priority and non-priority traits, with better results for priority traits in the UK and better results for non-priority traits in Ukraine. In Poland, there is a significant difference in the level of quality of internationalisa