The primary aim of this study was to evaluate the parenting component of the Youth Horizon Trust programme for families of young people with severe conduct disorder. Empirical research supports the assertion that interventions designed to change parental discipline practices are the most effective interventions in reducing conduct problem behaviour in young people. Eleven parents of Youth Horizon Trust programme participants completed a multi-method questionnaire conducted with repeated assessments over a twelve week period. The constructs measured have been consistently linked to conduct disorder. The questionnaires and a similar evaluation method were used in prior North American research (Frick, Christian, & Wootton, 1999; Shelton, Frick, & Wootton, 1996). The present study was designed to determine whether there were differences in parenting practices during a three month portion of intervention (hypothesis 1), among parents in the first, second and third years of programme participation (hypothesis 2), towards the end of programme involvement, compared to parents early in the programme (hypothesis 3) and related to the level of the young person's distress at the time of intake (hypothesis 4). The present study found firstly, that the two positive parenting scale results differed from prior research but the three negative parenting subscales showed similarities in the direction of changes (Frick et al., 1999). Secondly, there was no overall relationship between the time duration of the intervention and improvement in parenting practices, but changes in the third year indicated reductions in negative parenting practices and improved parental involvement, monitoring, supervision, and consistency. In addition, the most distressed young people at the beginning of the treatment programme had parents who indicated less involvement in their parenting practices. The overall implication drawn from the findings is that improvement in supervision, monitoring, and consistency of discipline by parents are more readily adopted than involvement and positive parenting practices. Further research with more extensive monitoring, larger samples and over a greater time frame are discussed.