Juvenile idiopathic arthritis (JIA), as a chronic condition, is associated with significant disease- and treatment-related morbidity, thus impacting children's quality of life. In order to optimize JIA management and to ensure the best possible care and outcome for children with rheumatic diseases, dedicated disease activity and damage assessment tools are essential. In recent years, there has been a concerted and important international effort to develop and validate disease activity and outcome instruments specific to JIA. This update aims to describe the main outcome measures currently used in JIA patients. These outcome measures include composite disease activity score, measures of physical function, measures of health related quality of life, clinical measures of damage and the assessment of Parent and child reported outcomes (PCROs).