The Education and Manpower Bureau (now known as the Education Bureau) announced in 2005 that the three-year senior secondary education system was implemented at Secondary Four in September 2009. Under the new academic system, all students are expected to complete three years of junior secondary education followed by three years of senior secondary education. Students entering Secondary One in September 2006 sit for the first Hong Kong Diploma of Secondary Education (HKDSE) Examination in 2012, after completing six years of secondary education. In 2012, about 73,000 candidates entered for the examination. About 72,000 of them are school candidates and about 1,000 are private candidates.

Most school candidates take four core subjects (Chinese Language, English Language, Mathematics and Liberal Studies), plus two or three elective subjects in the HKDSE. The HKDSE makes use of Standards-referenced Reporting of assessments. Standards-referencing aims at reporting candidates' results against a set of prescribed levels of achievement based on typical performance of candidates at those levels. For each of the levels, a set of descriptors has been developed that describes what the typical candidate performing at this level is able to do. Candidate's results indicate the standards achieved in terms of knowledge and skills regardless of the performance of the other candidates taking the same examination. This reporting system also enables stakeholders to understand explicitly what the candidates know and can do when they have achieved a certain level of performance. The results are expressed in terms of five levels of performance, of which 5 is the highest and 1 the lowest. The Level 5 candidates with the best performance will be awarded a 5**, and the next top group awarded a 5*. A performance below Level 1 will be labelled as "Unclassified".