This chapter, based on documental and bibliographical research, discusses PISA and its influence on Brazilian public policies on education from the analysis of the country’s main curricular document: the National Common Curricular Base, BNCC (in the Portuguese acronym), approved in 2018. To this end, the core conceptions that structure the three tests of PISA, and its changes from 2000 to 2020, will be presented and discussed. Some of the weaknesses of its results will also be discussed on the basis of the descriptions of the proficiency scales, one of the ways used to disseminate and explain its results. As example of the influence PISA has over the initiatives carried out in several countries, the process of formulation of the BNCC, from 1995 to 2018, will be discussed as well as the main disputes that arose during this process. Moreover, the conceptions of PISA present in its formulation are discussed as well as the emphasis given to external assessment as a way to implement the BNCC. The analysis shows that the two instruments, albeit different in nature, are defined as inducers of the improvement in education standards and do so from the results of the tests and the incentive to compete for better results.