56 Background: Mammographic breast density is a significant risk factor for breast cancer. Women with extremely dense breasts are at 4-to-6 times the risk of developing breast cancer than women with primarily fatty breast tissue. Electrical Breast Densitometry (EBD) is a new technique that assesses breast density. EBD is non-ionizing, fast, has low cost per test ($20-$30) and may help in breast cancer risk assessment in the primary care setting. Methods: This study evaluated the feasibility of the EBD in an IRB-approved pilot study of 20 patients. The study used a custom-made self-adhesive electrode (SenoSENSE Medical Systems, Toronto, Canada) interfaced to an off-the-shelf impedance meter (Bodystat 1500, Bodystat, Isle of Man, UK) with a customized cable. On the same day as the subject’s scheduled mammogram, impedance measurements were acquired for each breast. Mammogram densities were scored by a trained radiologist using standard BiRADS breast density categories 1 to 4. Results: A high correlation coefficient was observed (Pearson correlation coefficient >0.80) between breast density determined by the EBD and the BiRADS breast density score. In addition a statistically significant difference was observed between dense categories (BiRADS 3,4) and fatty categories (BiRADS 1,2) (p<0.01), as well as between extremely dense breasts (BiRADS 4) and all other categories (p<0.01). Very high correlation (Pearson correlation coefficient >0.95) was observed between EBD measurements on the left and right breasts. Previous studies have reported a left/right correlation of 0.89 for blinded mammography readers. Conclusions: These results suggests that the EBD measure may be less variable than mammographic estimates of density. The results of the study suggest that Electrical Breast Densitometry is a promising technique for the assessment of breast density and the ability to aid in evaluation of breast cancer risk. It can be reasonably deployed at primary care facilities.