Pediatric patients with chronic illnesses or diseases or who require long-term nutrition support are most vulnerable to nutrition-related issues. Malnutrition in a pediatric patient may negatively affect long-term growth and development. Children also become malnourished much more quickly than adults. A comprehensive nutrition assessment that includes food and nutrition-related history, anthropometric measurements, biochemical data, medical tests and procedures, nutrition-focused physical findings, and patient history should be completed on these patients as no one parameter is a comprehensive indicator of nutrition status. Anthropometric measurements provide important information on the growth and nutrition status of a child, yet many times it is difficult to get accurate and valid measurements due to physical limitations of the child or improper technique. Inaccurate measurements may result in a missed diagnosis of malnutrition or may lead to an incorrect diagnosis of a healthy child. Knowledge of appropriate anthropometric measurements and alternatives is crucial when assessing growth in all children and essential for those who are physically handicapped or critically ill. The purpose of this review is to present key components of a pediatric nutrition assessment so proper nutrition-related diagnosis, including malnutrition, can be accomplished, a nutrition care plan established, and expected outcomes documented.