Background: School management, in Ireland and also internationally, are currently faced with the problem of peer aggression among students both in a traditional school context and in a cyber context. Although Irish school principals are obliged to implement policy and procedures to counter bullying among students, there is a need for guidance that relates specifically to cyber-based peer aggression. Purpose: The present research was conducted in order to assess Irish post-primary school principals' methods of addressing both forms of peer aggression through school policy and procedures in the absence of cyber-specific guidelines. Sample: A sample of 45 post-primary school principals in Ireland responded to the research. Design and methods: A questionnaire study was undertaken in spring 2011 and a broad sampling frame was applied, with members of the National Association of Principals and Deputy Principals (N = 584) invited to respond to the research online. Following a low response rate, 12% of the entire population of post-primary school principals (N = 712) were invited to respond via a postal survey. Although both quantitative and qualitative data were collected, the present research approach is predominantly qualitative. Quantitative data were examined using descriptive statistics, whilst thematic analysis of qualitative data was conducted. Results: It emerged that all respondents implemented policy to counter traditional bullying and the majority (32 of 44 respondents) addressed cyberbullying within this policy. It was evident that a number of respondents were attempting to provide training for pupils, parents and teachers in relation to traditional bullying, cyberbullying and cyber safety. However, there was great disparity with regard to the training approaches. With respect to cyberbullying specifically, principals indicated a need for greater support from the Department of Education and Skills in relation to training, resources, guidance and information. Conclusions: It was evident that further guidance and support is required from the Department of Education and Skills to assist Irish post-primary school principals in countering cyberbullying. The current research also had implications for conducting research online with school personnel.