A variety of tools are currently available for assessing the various aspects of fetal maturation. Assuring mature neonatal pulmonary function is the goal of maturity testing, and specific test procedures are available to meet this need. The procedures vary from rapid screening tests to very specific phospholipid profiles that incorporate phosphatidylglycerol analysis. One may select from the various procedures those best suited to the clinical needs of a particular patient and the resources of a given institution. Consequently, the inadvertent delivery of a premature infant should no longer occur.