Unmet needs scales are a way of eliciting cancer patients’ perceptions of their need for help in order to achieve optimal psychosocial wellbeing. This represents a bottom-up approach to the assessment of psychosocial wellbeing. It may be used in conjunction with traditional top-down, expert driven methods of conceptualising psychosocial status. While there has been an expansion in the development of unmet needs scales for cancer patients, survivors and significant others, there remains a need to ensure that these measures are psychometrically robust. Predictive validity, in particular, has been largely unexamined. More work is needed to establish the clinical utility of unmet need scales and how to define what represents meaningful changes on these measures.