The article describes the Czech party system and its development over time using data from the annual financial reports of political parties and seeks to contribute to the domestic debate on the transformation of Czech political parties since 1989. The article distinguishes three factors that caused political party budgets to change – the economy, regulation, and strategy – and proposes a simple theoretical model with which to interpret and understand data obtained from the accounting books of political parties. It also presents a new three-dimensional typology of political parties based on the size of a party budget and the structure of party revenue and expenditures. The article concludes by arguing that understanding how all three of the aforementioned factors intersect could be useful for predicting the future development of party competition in the Czech Republic and facilitate the application of the ideas proposed herein to party systems abroad.