This report describes a new standard technique for the measurement of esophageal pressure (Pes) in mechanically ventilated neonates. A neonatal esophageal balloon was positioned in the distal esophagus and inflated with a volume of air determined by static pressure volume curves. Different waveforms demonstrating cardiac contractions, mechanical inspiration, spontaneous breathing, and myoclonic jerks were observed. Measurements made in the supine position were higher than those made in either the right or left lateral position (p less than 0.005). Pes measurements increased notably with barotrauma (p less than 0.025).