Objective: In order to determine the utility of functional outcome measures in children with chronic arthritis, we compared the results of two well-validated measures, the Childhood Health Assessment Questionnaire(CHAQ) and the Functional Status II (FSII[R]). Methods: Sixty-eight mothers of children with chronic arthritis, ages 1 to 16 years, completed the CHAQ, an arthritis-specific measure that includes two visual analog scales to assess pain and global well-being and the FSII(R), a general instrument used in children with chronic physical conditions, that assesses general health, locomotion and interpersonal functioning. At the same visit, a pediatric rheumatologist examined each child for number of active joints and number of joints with limited range of motion, and completed a visual analog scale of global disease activity. Results: Both measures had significant associations with the physician's assessment (r=0.60 for the CHAQ and 0.50 for the FSII[R]), and with each other (r=0.67). CHAQ scores were most strongly associated with the number of limited joints (r=0.62), followed by the parent's assessment of global well-being (r=0.49), the number of active joints(r=0.48), and the parent's assessment of overall pain (r=0.48). In contrast, the FSII(R) scores were most strongly associated with the parent's assessment of pain (r=0.63), followed by the parents assessment of global well-being(r=0.59), and less strongly with the number of active and limited joints(r=0.42 for each). All had p<0.02. Conclusion: We conclude that both an arthritis-specific measure (CHAQ) and a general measure of functional status (FSII[R]) are good measures of function in children with chronic arthritis. The CHAQ is more strongly associated with physician's global assessment, and the number of active and limited joints, while the FSII(R) is most strongly associated with parent's assessment of pain and global well-being. Because these measures provide complementary information, they are both useful tools in assessing children's functioning.