Paediatric psycho-oncology is an evolving speciality and is increasingly being recognised as an essential component in children’s cancer care. Modern paediatric oncology services aspire to integrate physical care with psycho-social care and build capacity within clinical teams to address the emotional needs of parents and children side by side with other aspects of medical care. This article discusses the unique challenges of paediatric psycho-oncology and common situations where psychological assessment and management of children and young people with cancer become especially important. The authors propose a tiered structure of training. Providing empathic evidence-based psycho-social care is ‘everyone’s business’ in paediatric oncology and not merely that of mental health professionals. However, there are times when a more specialist intervention by a paediatric liaison psychiatrist and/or a clinical psychologist is needed for optimum outcome. Learning interviewing techniques suitable for children and adolescents should be a core part of the training in paediatric psycho-oncology. Professionals should be encouraged to reflect on their own emotional wellbeing, which in turn will provide a stable foundation of emotionally matured care to children, young people and their families.