The practice of pediatric laboratory medicine involves unique challenges related to development, nutrition, growth, and diseases during different periods of infancy, childhood, and adolescence. This article discusses key aspects of pediatric laboratory medicine faced by clinical pathologists, clinical laboratory scientists, and clinicians, including point-of-care testing, preanalytic variables, analytic factors, age-specific reference intervals, esoteric laboratory tests, clinical impact, andfuture opportunities. Although challenging, pediatric laboratory testing offers many opportunities for improved patient care, clinical- and laboratory-based research, and education.