A report released by the South African Council of Educators (SACE) (2011:12) reveals a grim picture on school safety and the shocking results showing that 1.8 million learners experienced violence at school. Eight years after the Human Rights Watch World Report (2008:164), sexual violence, corporal punishment; bullying, gang-related activities, and occasional murder continue to plague some South African schools. Violence against children and youth has reached endemic proportions in South Africa (Huisman, 2014:10). The goal of the study was to develop, implement and evaluate a school-based violence prevention programme with high school learners in Tshwane South District. The bio-ecological systems theory and a combination of practice approaches, namely: the developmental social work approach, the social and emotional learning (SEL) approach, character education (CE) and social cognitive and social competence perspective were utilised as theoretical frameworks for the study. The study was embedded within the pragmatic and critical research paradigms. The Intervention Research, Design and Development (D&D) model which is a sub-type of applied research, was utilised for the study. The exploratory convergent design was used, starting with the exploratory design and followed by the descriptive design (Creswell & Plano Clark, 2007:59). For the qualitative phase, the collective case study method was used to solicit in-depth views of learners on the school violence problem and interventions to address the problem (Creswell & Plano Clark, 2007:59). During the quantitative phase, the descriptive survey research design was employed to identify and describe the nature and aetiology of the phenomena of school violence (Onwuegbuzie & Leech, 2006:474) and to obtain quantitative data about the learners' opinions, attitudes, and experiences of school-based violence (Engel & Schutt, 2013:18). Concurrent multilevel sampling was employed (Sharp, Mobley, Hammond, Withington, Drew, Stringfield & Stipanovic, 2012:35), including both purposive and random sampling techniques (Teddlie & Yu, 2007:85). In developing the Triple T school-based violence prevention programme in collaboration with learners as service users, Lipsey's Theory-Based Programme Development and Evaluation Model was utilised (Lipsey, 1993:33). Mixed methods, namely a One-Group Pretest-Posttest design in combination with a focus group interview was used to evaluate the programme. The Triple T programme was effective in enhancing learners' knowledge of the nature, causes and impact of violence; their knowledge of moral values and ethical principles; their understanding that violence is a violation of human rights; the importance of caring, compassionate and supportive interpersonal relationships that are based on respect and UBUNTU principles; and increased their knowledge of conflict resolution and anger control strategies. Although some skills in problem-solving and decision-making were learnt, time constraints did not allow in-depth skills development. Furthermore, the use of ICT and role play was unproductive and there was a lack of preference for homework exercises. It cannot be confirmed that the programme has been effective in changing learners' attitudes and behaviours because change is a process and happens over time. Based on the study's findings, it is recommended that the programme be modified, improved, and then implemented and evaluated pertaining to the promotion of an anti-violence school culture and the prevention of violence. / Thesis (DPhil)--University of Pretoria, 2016. / Social Work and Criminology / DPhil / Unrestricted