Istvan started his career at Ammirati Puris Lintas as an Art Director.
Later he worked at Saatchi & Saatchi, DDB and he was Executive Creative Director at JWT.
After this, he set up the independent ad agency White Rabbit with his partners where he has been working for more than ten years.

His creative work won him numerous domestic and international awards like D&AD, Cannes Lions, One Show, Clio, LIA, ADC Global, AdStars, New York Festivals, Mobius Awards, Kinsale Sharks, One Screen, Epica, Cresta Awrads, Brand Film Festival London, AdAge, Golden Award of Montreux, Lisbon International Advertising Festival, Golden Hammer, Golden Drum, PIAF, KIAF, White Square, AdBlackSea, Chip Shop and several Effies – including a Grand Prix (which made White Rabbit the 75th most efficient independent agency in the world).

He was a member of the jury at Cannes Young Lions, AdStars, New York Festivals, Mobius Awards, Cresta, Golden Award of Montreux, Lisbon International Advertising Festival, KIAF, Creativity International and Newstars.
He is member of D&AD, The One Club, Art Directors Club Global and Creative Circle.
He is an examiner at VISART Academy Of Arts.
Among his other achievements:
The most remembered TV commercial in the UK (AdWatch/TNS Iternational):
Cillit Bang – The dirt is gone!  (Berry Scott) / JWT Budapest
The most effective nationwide campaign in 2011 (Effie Grand Prix): Heineken Hungaria / White Rabbit Budapest
The first ever Luerzer’s Archive cover featuring a work from Hungary / White Rabbit Budapest
When he is not making ads, he likes to listen to his collection of vinyl records, take care of his exotic houseplants or count clouds. He happily opens a bottle of good wine to accompany any of these activities.