The purpose of this study was to determine if the U.S. National Institutes of Health Diabetes Prevention Program (DPP) could be successfully implemented in a worksite setting. Thirty-seven adult employees of BD Medical Systems of Sandy, Utah were enrolled in a single-group time-series study using the DPP. Two-hour oral glucose tolerance tests (OGTT) and other outcomes were measured at baseline, 6 months, and 12 months. Weight, body mass index, waist circumference, 2-hour OGTT, very low density lipoproteins, triglycerides, and aerobic fitness were significantly improved at 6 and 12 months and showed overall significant improvement across time. Fasting blood insulin, total cholesterol, low density lipoproteins, and total cholesterol/high density lipoproteins ratio were significantly improved at 6 months, but not at 12 months. Eighteen of the program participants (51%) were no longer in the pre-diabetes and diabetes categories after 1 year. Existing worksite health promotion and occupational health professionals can successfully offer the DPP and help employees improve glucose tolerance.