The book namely "Vietnamese rhythm and traditional music" is a scientific project at fundamental level of the Vietnamese institute for musicology done by Musician- Eminent teacher Hoang Kieu. The book was published by the Vietnamese Institute for Musicology in 2001. It is divided into introduction, the first part, the second part and conclusion.

* The introduction, the author only introduces the two main music elements: Vietnamese rhythm and Vietnamese musical rules.

* The first part, Vietnamese traditional music. Musical rule - Mode. This part includes 3 chapters.

- Chapter 1: Vietnamese music related Musical rules. Chinese musical rule is introduced quite thoroughly from legend of its formation to methods and laws. The author also provides readers with different musical rules, such as Persian and Indian musical ones and equal temperament, etc.

- Chapter 2: Vietnamese traditional mode, the author inhesitately focuses on the rule of Yin and Yang - The five basic elements. For the author, they exert great influence on the formation of pentatonic scale of Vietnam.

- Chapter 3: The relationship between pentatonic scales of Vietnam and those of Northeast Asian countries, under the headings The pentatonic scale of China, The pentatonic scale of Korea and The pentatonic scale of Japan, the author provides the readers with attractive information on the relation of scale system of some countries having the scale system nearly the same as that of Vietnam.

* The second part: Vietnamese rhythm - the formation of traditional songs, having two chapters.

- The first chapter namely Influence of rhythm on poetry and music. The readers can study poetry styles in music, great influence of Vietnamese rhythm on music, factors forming melody, such as legato tone, stress, rhyming, etc. in more details.

- Rhythm of traditional song is the heading of chapter 5, the last chapter of the project. It includes 5 headings, such as Form in traditional music, Auxiliary word, Technique for setting poem and structure, Combination of rhythm-poem-music in forming song. It can be said that the author actually gathers up his mind to analyze and illustrate this specific characteristic forming Vietnamese traditional music nature in this chapter.

* Conclusion: It is clear that conclusion is a part to sum up all researched matters and present evaluations to identify value of studied objective.

500-page book has many matters, some were studied thoroughly, some were only introductions and some were not mentioned bravely because of lack of data to demonstrate. However, the readers still admire because Vietnamese rhythm and traditional music research done by musician Hoang Kieu" is a worthy project in researching ethnomusicology", said Prof. Dr. Nguyen Phuc Linh and "It is a very enthusiastic project of the musician Hoang Kieu for many years, matters he mentioned are also of urgent and deep concern of the current researchers" (Asso.Prof. Dr. Pham Minh Khang).

With the permission of the Publishing Department of the Ministry of Culture and Information, the Vietnamese Institute for Musicology publishes this project. It is hoped that the project written by "a life time" is widely spread to students and researchers inside and outside musical branch.