Zero is a schoolwide antibullying program developed by the Centre for Behavioural Research at the University of Stavanger, Norway. It is based on three main principles: a zero vision of bullying, collective commitment among all employees at the school using the program, and continuing work. Based on these principles, the program aims to reduce student bullying by increasing the school's ability to uncover and stop bullying, and eventually to prevent it. The Zero program was launched in 2003, but the work that led to it goes back to the first national steps against bullying in 1983. The program extends over sixteen months as teachers develop their awareness of bullying and their competence in addressing it. Students and parents are involved in the program as well. The role of the school leadership is very important. More than 360 Norwegian schools have carried out the program.