He became director of the Dohnányi Orchestra Budafok, one of the youngest professional Hungarian orchestras in 1989. Under the direction of Gábor Hollerung, the youth orchestra matured to a professional ensemble in a matter of years and has advanced to acquire a well-deserved position among the leading orchestras of Hungarian classical music.
Budapest Academic Choral Society – since 1980, he has been artistic director and leading conductor of the choir established in 1957. In the last few decades, the choir has grown to be a noteworthy ensemble of the capital of Hungary, having won several national and international competitions, being a regular performer at international musical events and contributing to performances of professional orchestras around the world.
Budapest International Choir Competition – in 1988, Gábor Hollerung was one of the key initiators of establishing a choir competition with a new artistic concept in Budapest. Since then, the competition, organized every two years, has evolved into an internationally ranked event and has served as a model for several other international choir contests.
„Let the country sing” –This extremely popular musical event, which boasts a tradition of over 20 years was initiated by Gábor Hollerung in order to offer amateur ensembles and individuals the opportunity of rehearsing and performing classical and modern masterpieces in a professional milieu, with the contribution of the Budapest Academic Choral Society and the Dohnányi Orchestra.
Interkultur Hungária – Gábor Hollerung is artistic director of the company established in 1998, which organizes national and international musical events worldwide including the Budapest International Choir Competition, the Choir Olympics and the Zemplén Festival
MAKOFESZ (Association of Hungarian Choir Competitions and Festivals) – Gábor Hollerung was the first chairman of the association established in 1998, he is presently co-chairman.
„Music to comprehend” – This exceptional concert series targeting families and younger generations performed by the Dohnányi Orchestra and conducted by Gábor Hollerung enjoys ever-increasing popularity. These concerts pursue the Bernstein model, offering a quality musical performance accompanied by easily comprehensible explanations of the musical material.
Guest performances – Gábor Hollerung has been hosting conductor courses in Hungary and abroad every year since 1986. He has performed as guest conductor all over the world: besides his invitations to European and American events, he is frequently onstage at the concert halls of Israel and Taiwan.
Zemplén Festival – he attained the position of artistic director of this renowned festival in 2004. The 15 year-old festival is an annual event of great tradition, convening all artistic genres, involving a wide range of performances and is organized every August at towns and villages located in the Zemplén Hills.