Abstract
This article aims to analyse changes of the Slovak party system from 1992 to the last parliamentary elections of 2020. These elections were the eighth elections in the history of independent Slovakia.
There are discussions about stability or instability of individual development stages of the party system. In the article, attention is paid to changes in the distribution of forces within the development of the party system.
In political science, various methods are used to measure the party system's dynamics to determine the intensity of changes and the trends arising from them. This analysis is based on election results in each electoral cycle (period), which are being compared.
Next part of the analysis is focused on the selected comparative indicators: Index of the Effective Number of Parties and Aggregation Index. These indices are chosen based on the criteria of classification of party systems.
The results presented in the final part of the paper prove that several significant milestones in development of party system could be identified, as confirmed by the 2020 general elections - a major breakthrough in development trends.