The relationship between transcutaneous oxygen tension (tcpO2:) and sucking opportunities in noncrying, preterm neonates was investigated. Twenty-six measurements of nonnutritive sucking and its relationship to tcpO2 were collected on 11 neonates who were monitored continuously for tcpO2. Of the 26, 10 sets of measurements were recorded on 6 neonates receiving assisted ventilation, and 16 were recorded on 4 neonates breathing room air. One neonate was measured one time on assisted ventilation and two times breathing room air. The design consisted of three 8-minute time periods: pretreatment, treatment (sucking opportunities). and posttreatment. There was a significant relationship between the pretreatment-treatment and treatment-posttreatment tcpO2 levels (both at p < .01). These results suggest that sucking facilitates more adequate oxygenation in noncrying, preterm neonates.