The International Classification of Functioning, Disability and Health (ICF) and its version for children and youth, the ICF-CY, can contribute to the present knowledge on the lives of young children with cancer, with an international and interdisciplinary language. In this context, the term health can be seen as a multidimensional concept in which both illness and non-illness/well-being are dimensions that can be present at the same time, rather than two opposite concepts. Health is the result of a continuous process rather than something that one individual has; it is a resource for everyday life rather than the objective of living (WHO, 1986). The ICF was developed to classify different dimensions on individuals’ health as a unified standardised common language and framework, to be used across disciplines (WHO, 2007). It acknowledges that health and illness are complex concepts and promotes a biopsychosocial model of health, in which the context is as important as the individual and his/her needs. The view of health as functioning in everyday life can be operationalised using the ICF model of body structure, body function, activities and participation and environmental factors (Rosenbaum & Gorter, 2012).