Hepatitis C virus (HCV) infections go largely undetected due to their asymptomatic nature. It is believed that fewer than half of existing cases are detected by surveillance systems. Further confusion in surveillance may arise in that acute and chronic infections are often handled separately. This evaluation will look at the simplicity, flexibility, data quality, acceptability, sensitivity, positive predictive value, representativeness, timeliness, and stability of HCV surveillance in Washington State. The evaluation is currently in progress and preliminary results are expected to be formulated by November.