Zero is developed by Centre for behavioural research (now Norwegian Centre for Learning Environment and Behavioural Research) at the University of Stavanger in Norway.
Since 2003, more than 400 schools in Norway have participated in Zero.
Zero is spread to Chile and the US.
The programme instructs school staff how to reveal bullying, solve bullying cases, prevent bullying and integrate anti-bullying efforts in general schoolwork.
Zero involves the students in active work for an environment free of bullying. The student government gets a special responsibility. Also parents are involved as supporters of the efforts.