The chapter presents an analysis of the application of the proportionality doctrine in the case law of the Polish Constitutional Tribunal. Based on both a qualitative and quantitative analysis of a large sample of case law applying proportionality, the chapter uses quantitative indicators to provide an overview of the characteristics of proportionality analysis in action, including the rights and subject matters to which proportionality is applied, the division of labour between the stages of the analysis when striking down measures, and termination rates for each stage following a failure. The findings demonstrate that contrary to the common conception, nearly a quarter of the cases struck down failed to meet the requirement of the legitimate aim stage. In addition, although the Tribunal only rarely strikes down a law without considering the test of proportionality in the strict sense, in most cases this final stage does not carry the burden of a failure alone: failures are typically based on a combination of both the necessity and strict proportionality tests. The chapter further analyses qualitatively the formulations and applications in practice of each of proportionality's subtests, exposing the range of interpretations given and the content that has been infused into the different stages.