This is the essential "how to guide" for low-intensity mental health trainees, practitioners and service supervisors who support children and young people with mild-moderate anxiety, depression and behavioural difficulties. It provides a manual for practice covering assessment, decision-making and key interventions, with step-by-step guidance, case vignettes and accompanying worksheets to support each evidence-based intervention. It also offers guidance on key service implementation principles, supervision and adaptations to practice. It is an ideal resource for those in low-intensity training, practitioner or leadership roles, looking to develop competency in the low-intensity cognitive behavioural clinical method.