OBJECTIVE: To investigate the influence of ocean sounds (white noise) on the night sleep pattern of postoperative coronary artery bypass graft (CABG) patients after transfer from an intensive care unit. DESIGN: A before and after trial with an experimental and a control group was used in this intervention study. SETTING: A large public hospital with primary, secondary, and tertiary care facilities. PATIENTS: A consecutive sample of 60 first-time CABG patients was systematically assigned to the experimental or the control group. INTERVENTION: For the experimental group, the sounds were played on the Marsona Sound Conditioner (Marpac Corporation, Wilmington, NC) for three consecutive nights posttransfer from the ICU. No control of environment, except for the elimination of white noise, was done for the control group. MAIN OUTCOME MEASURES: The Richards-Campbell Sleep Questionnaire, a visual analog scale, provided self-reported sleep scores on six variables. Analysis of covariance was used to test the difference between the posttest scores of the groups, with the pretest used as the covariate. RESULTS: There were significant differences in sleep depth, awakening, return to sleep, quality of sleep, and total sleep scores; the group receiving ocean sounds reported higher scores, indicating better sleep. There was no difference in the falling asleep scores. CONCLUSION: The use of ocean sounds is a viable intervention to foster optimal sleep patterns in postoperative CABG patients after transfer from the ICU.