Failure-to-thrive (FTT) is a chronic symptom accounting for 1% of all patients admitted to pediatric hospitals. FTT, which is traditionally attributed to organic (OFTT) and/or nonorganic (NFTT) causes, results in undernutrition. Undernutrition has potentially serious effects on child development, behavior, and cognitive skills. We undertook a study of children with FTT to determine whether multidisciplinary team treatment resulted in improved weight gain compared with children treated in a primary care setting. Fifty-three children with NFTT referred to our outpatient FTT consultative clinic and 107 children with NFTT identified as comparison subjects from our primary care clinic (PCC) were enrolled in the study. Growth outcomes over a 6-month follow-up were analyzed using growth quotient (GQ) analysis. Children followed in the multidisciplinary team clinic grew better (GQ = 1.75 +/- 0.39 SD) than did children in the PCC (GQ = 1.18 +/- 0.42 SD, p less than .001). The use of a multidisciplinary team offers special advantages in the rapid correction of undernutrition in children with NFTT.