The Zeugnis über die Zentrale Oberstufenprüfung (ZOP) (pronounced [t͡sɛnˈtʁaːlə oːbɐˈʃtuːfn̩ˌpʁyːfʊŋ]) is a Goethe Institute certificate proving high-level German language ability. The ZOP is rated at level C2 of the Common European Framework of Reference for Languages (CEFR) — C2, the highest of the CEFR levels, signals a level of language ability comparable to an educated native speaker. The Zentrale Oberstufenprüfung requires the examinee to understand difficult texts and to adroitly communicate in both spoken and written language.
Possessing a ZOP cerfication is considered valid proof of German language proficiency for anyone seeking entry into a German Hochschule or university. It is also valued as a qualification proving mastery of German in business contexts.
The Zentrale Oberstufenprüfung may only be administered to persons at least 16 years old who have not learned German as a native speaker.