An increasing amount of polysomnographic studies are performed in early infancy. Complete pediatric sleep laboratory systems are commercially available and provide fast and exhaustive results if operated by trained personnel. Experience in evaluation is necessary, because a broad range of possible diagnostic findings exists, and artifacts are common. Based on longitudinal studies in 31 healthy infants, we present reference values for several polysomnographic parameters. Aberrant results must be interpreted in the context of patient's history, clinical state, and additional laboratory findings. In presence of a clearly defmed indication for polysomnographic testing, clear therapeutic and interventional strategies can be derived. Possible consequences include the stimulation of the respiratory drive by drugs with subsequent polysomnographic control of therapeutic effect, a transfusion, the prescription of a home monitor, and the recommendation of further diagnostics or of control polysomnographies. In conclusion, infant polysomnography is an important diagnostic tool in pediatrics.