Cognitive behavioural approaches emphasize the links between thoughts, feelings and behaviour (Greig, 2007). Previous research has indicated that these approaches are efficacious in reducing disruptive behaviour in adolescents. The aim of the current study was to provide further evaluation of cognitive behavioural group work to reduce disruptive behaviour with this population and to determine if improvements made were maintained in the longer term. The sample comprised 22 adolescents aged 13-to 14-years-old identified by school staff as displaying disruptive behaviour (Cameron, 1998). A curriculum based on Squires (2001), using key cognitive behavioural approaches, was delivered over a seven-week period to the participants. Participant, parent, and teacher ratings on the Strengths and Difficulties Questionnaire (SDQ) immediately after the intervention all indicated significant reductions in disruptive behaviour. Other positive effects included enhanced ratings of self-concept on the Beck Youth Inventories, 2nd Edition and trait emotional intelligence on the Trait Emotional Intelligence Questionnaire-Adolescent Short Form (TEIQue-ASF). Improvements in behaviour and self-concept were maintained at six-month follow-up according to participant and teacher ratings. However, parent ratings of behaviour had returned to pre-intervention levels. Further research, with different age groups and demographic populations along with concurrent parent programmes is recommended.