The glycosylated hemoglobin assay is a relatively new test used in the diagnosis and monitoring of the diabetic patient. This assay should be of interest to the periodontist as it offers important advantages over traditional blood glucose testing methods. Most importantly, it gives an indication of the blood glucose level over an extended period of time (30 to 90 days), whereas traditional assays only indicate the glucose level at one point in time. Additionally, there is no requirement for fasting prior to testing. Two case reports are presented to illustrate how the glycosylated hemoglobin assay can be utilized by the periodontist.