The purpose of this study was to describe the nature and frequency of sleep pattern disturbances in patients post coronary artery bypass (CABG) surgery. An exploratory design using telephone interviews at one week, one month, three months and six months was used to describe the incidence and nature of sleep disturbances post CABG surgery. Forty-nine patients completed all four measurement times. More than half of the patients reported sleep disturbances at each measurement time. Sleep disturbances during the first month post CABG were reported to be the result of incisional pain, difficulty finding a comfortable position and nocturia. Although less frequent over time, these problems persisted for six months. The authors propose nursing interventions to improve sleep post CABG surgery. Implications for continuing research are discussed.