Aim To evaluate the feasibility and effect of a 10-session creative arts in psychotherapy group programme on posttraumatic stress symptoms, behavioural problems, and posttraumatic growth, in children who experienced a traumatic event. Design A multicentre non-randomized controlled trial with a treatment and a control condition conducted in South Africa (4 sites). Methods 125 children aged 7 to 13 years were assigned either to the treatment condition receiving creative arts in psychotherapy or a control condition with a low-level supportive programme without treatment. Attrition rates were 63.4% and in total 47 children completed the programme and questionnaires assessing posttraumatic stress, posttraumatic growth and behaviour problems both at baseline and follow-up; 23 in the treatment group and 24 in the control group. Adjusted mean differences were analysed using ANCOVA with bootstrapping. Results Results showed that both hyperarousal symptoms ( d = 0.61) and avoidance symptoms ( d = 0.41) decreased more in the treatment group compared to the control group. There was no significant effect of the intervention found for reported levels of behavioural problems and posttraumatic growth. Conclusion In spite of severe challenges implementing and executing this pioneering study in underprivileged areas of South Africa, support was found for creative arts in psychotherapy reducing hyperarousal and avoidance symptoms, but not for other symptoms. Valuable lessons were learned on feasibility of implementing this intervention in a developing context.