『National Korean 5 Sets』 is an advanced textbook for learners who have studied Korean for approximately 800 hours.
The basic textbook consists of two volumes, 『National Korean 5-1』 and 『National Korean 5-2』, and each volume is designed to enable learning in an integrated manner involving reading, listening, writing, and speaking activities.
In the appendix of the separate volume, 『Grammar, Vocabulary, and Expression Collection』, the target grammar, core vocabulary, and expressions covered in the basic textbook are presented with various examples to help learners understand grammar more deeply and minimize errors.

This textbook focuses on developing learners' ability to communicate formally in formal contexts.
Additionally, it aims to improve communication skills on social and abstract topics and areas related to work or study, and to broaden understanding of cultural diversity and uniqueness by comparing various aspects of Korean culture with one's own culture.