This paper reviews the three most commonly used measures of loneliness for children and adolescents (children: Loneliness and Aloneness Scale for Children and Adolescents [LACA] and Children ’ s Loneliness and Social Dissatisfaction Scale [CLS]; adolescents: UCLA Loneliness Scale [UCLA] and LACA). Loneliness is a pertinent issue across populations and affects the mental health and academic achievement of children and adolescents . To date, there has been no thorough examination of the loneliness measures for this age group . We examine how each of the three measures was developed, and assess the psychometric properties of those measures, gaining insight into whether they are valid and reliable assessments of loneliness . Results suggest that the UCLA Loneliness Scale is the most popular measure of loneliness for use with adolescents, but it does not have robust psychometric properties for that group . For children, the CLS appears most suitable . Results of the review identify gaps in aspects of measure development, with no measure having been developed with children or adolescents . Implications for future loneliness measurement research are considered.