Nurses at a large southwestern hospital undertook an initiative to optimize the preoperative skin preparation of patients undergoing open heart surgery. After an extensive review of the literature, a proposal was submitted to and accepted by the surgeons and internal review board of the hospital. High-risk patients were identified before surgery and randomized into groups to receive one of four different skin preps. The incidence of infection was lower in the two groups of patients who were prepped with insoluble iodine, indicating that the type of surgical skin prep could affect whether patients develop surgical site infections. The clinical practice of skin preparation in this hospital changed based on the results.