This article presents key features of the mathematics assessment in OECD’s Programme for International Student Assessment (PISA), from the point of view of the design of test items to fit in with the PISA mathematics framework. A brief description is first given to provide some background to the development of the PISA mathematics framework. The “spirit” of PISA mathematics is then captured through illustrative examples of items to highlight the differences between traditional mathematics assessments and PISA assessment. Some empirical data are presented to provide support for the claims of differences between PISA and other assessments. The PISA results for Hong Kong are also examined to highlight strengths and weaknesses of Hong Kong students. The main message that this article conveys is that PISA has taken a bold step in an international comparative study to link mathematics to the real world.