The mouth is one of the most hostile environments on earth, defended by secretions that some claim to be the ideal diagnostic fluids. The moisture of the mouth (or lack thereof) drives the disease processes that oral health-care professionals have come to know, love and despise. Yet, our frequent interaction with this fluid most often consists of suctioning it out of our way as quickly as possible. This course explores the science and diagnostic potential of oral fluids, helping dental professionals better understand saliva's role in disease processes and its value in patient care.