This book investigates the phenomena of school bullying and harassment. The research presented focuses on the question that among upper, primary school students and high school students, what kind of background factors may stand in the background of aggressive attitude and behavior patterns of school bullying. Due to the significant results obtained from this research, the authors were able to determine the background factors to help understand the process of the development of bully, victim, participant and bystander behavior patterns. They also allow for the development of the options of efficient mental hygiene.