Purpose: To systematically review research concerning parent-child agreement in health-related assessments to reveal overall agreement, directions of agreement, and the factors that affect agreement in ratings. Method: The Uni-Search and five additional databases were searched. Children's health issues were grouped into psychosocial issues including autism and ADHD, and physical and performance issues including pain. Measures used for comparison were those addressing (a) psychosocial functioning, (b) physical and performance functioning, and (c) health-related quality of life. Results: Totally, 39 studies met the inclusion criteria, comprising 44 analyses in all since four studies contained more than one analyses. Moderate child-parent agreement was demonstrated in 23 analyses and poor agreement in 20 analyses. Several analyses found more agreement on observable/external than on non-observable/internal domains. Overall, parents considered their children had more difficulties than did the children themselves, although there were indications that for children with physical performance issues, parents may underreport their children's difficulties in emotional functioning and pain. There were no consistencies in differences between children's and parent's ratings on levels of agreement with respect to the children's health issue, age or gender. Conclusions: Discrepancies between child and parent reports seem to reflect their different perspectives and not merely inaccuracy or bias. IMPLICATIONS FOR REHABILITATION In general, parents consider their children to have more difficulties - or more extensive difficulties than the children themselves think they have. The perspectives of the child and his or her parents should be sought whenever possible since both constitute important information concerning the child's health and well-being. Children with physical and performance issues reported more difficulties than their parents concerning the children's emotional functioning and pain. Clinicians should prioritize obtaining children's views on subjective aspects such as emotional issues as well as on pain.