The International Standard Classification of Education (I S C E D 1997) covers the following levels: level 0 - pre-primary education; level 1 - primary education or first stage of basic education; level 2 - lower secondary or second stage of basic education; level 3 - (upper) secondary education; level 4 - post-secondary non-tertiary education; level 5 - first stage of tertiary education; level 6 - second stage of tertiary education.
Rahvusvaheline ühtne hariduse liigitus ISCED 97 hõlmab järgmisi tasemeid: 0-tase − eelharidus; 1. tase − esimese taseme haridus, põhihariduse esimene aste; 2. tase − teise taseme hariduse alumine aste, põhihariduse ülemine aste; 3. tase − teise taseme haridus (ülemine aste); 4. tase − teise taseme järgne, kolmanda taseme eelne haridus; 5. tase − kolmanda taseme hariduse alumine aste; 6. tase − kolmanda taseme hariduse ülemine aste.