Assessment of mental health problems in children and young people (CYP) is an essential skill that requires a curious mind, a good knowledge of the subject and an ability to be empathic. Assessment should be structured with attention given to the developmental nature of the presenting difficulties and their impact on functioning. Similarly, understanding the impact of the child’s immediate environment on their mental health and integrating information from various sources is an important skill to be mastered. A thorough mental state examination of a CYP complimented by relevant physical examination is an integral component of a good assessment and creatively engaging a CYP in this process is crucial. A knowledge of psychometric profiles of various assessment and outcome measurement tools and the ability to skillfully use them in the assessment process is also important. The strength of child psychiatric assessments lies in multidisciplinary working. Specialist assessments by other professionals are valuable in arriving at a diagnosis or a formulation. The skill to sensitively feed this back to the CYP and their family, and engaging them in the next steps will help in a successful outcome. Ultimately, a good assessment ensures that the CYP and their families get the right help, at the right time from the right people.