Objectives:
The main objective of the article is to demonstrate the correlation between collaboration and the competitive position of universities. The specific objective is to show that the success of obtaining research project funding is linked to the level of international cooperation among competing universities, as well as the ratio of students to academic staff.

Material and methods:
The article adopts a quantitative approach, involving the analysis of statistical data related to selected types of public universities in Poland. The research scope includes research projects funded by the National Science Centre (NCN), publications in the Scopus database with co-authors affiliated with foreign institutions, and data collected through the European Tertiary Education Register (ETER) project. The study covers the period from 2011 to 2020.

Results:
The analysis examines the percentage of Scopus-indexed publications and the number of research projects funded by the NCN in different universities, as well as the ratio of students to academic staff. The analyses were conducted separately for universities participating in the Initiative of Excellence Research University (IDUB) project and other selected public universities.

Conclusions:
The conducted analyses have demonstrated a correlation between international cooperation and the competitive position of higher education institutions in securing research projects. This correlation, as well as the relationship between the success of obtaining research project funding and the ratio of students to academic staff, differs between research universities and others. It is justified to further enhance horizontal diversification in Polish higher education.