Most producers of patient level data - including diagnostic labs, many hospital nursing services, other reporting services, and clinical researchers - store their clinical observations electronically. However, data producers identify these observations with their own locally invented and idiosyncratic codes which many other systems do not understand. The resultant Babel is the main barrier to the deployment of effective and interoperable information and research systems - because they all need data from other systems to achieve their promise. Logical Observation Identifiers, Names, and Codes (LOINC) is a database of universal codes and names that if widely adopted would eliminate the Babel and the barrier. This lecture was videotaped and is archived at http://videocast.nih.gov/PastEvents.asp, search the archives for LOINC.