The purpose of the present study was to evaluate a bullying prevention program that involved eleven 90-minute, highly structured workshops conducted at the classroom level on a weekly basis. The intervention aimed to increase student awareness of bullying and its impact, increase empathy toward victims, and enhance positive attitudes toward school and academic achievement. Participants were 666 students who were selected from 20 elementary schools using stratified random-sampling procedures from a large metropolitan area of southern Greece. Students were randomly assigned to experimental and control groups and were provided measures of bullying and victimization behaviors at pretest and posttest (Olweus, 1996). Results indicated that there were statistically significant decreases in bullying and victimization behaviors from pretest to posttest. Specifically, victimization rates in the experimental group were reduced from pretest to posttest by 55.4%. The respective decreases in the control group were 23.3%. Similarly, bullying rates decreased by 55.6% at posttest compared with pretest in the experimental group, and the combined type decreased by 66.7%. Furthermore, a latent class analysis provided qualitative means on the specific categories in which decreases of negative behaviors were observed. Additional positive effects were observed with increases in positive attitudes toward school (school liking). We conclude that the current prevention program effectively reduced bullying and victimization in the elementary schools in Greece and holds promise for influencing the overall school experience.