Continuity of care depends on the availability of complete health care information on which current and future care can be planned and implemented. Consumers however, may have multiple records--even within single institutions--often unknown by the institution or the individual care provider. One of the first challenges to health care informatics professionals is to establish a means of identifying individual patients across care delivery systems. The ability to create an integrated record system depends on the development of a "universal person index" as well as considerations for standardizing and integrating other aspects of the electronic record. Many individual health facilities are working to create a "master person index" (MPI) and some integrated delivery systems are attempting to combine these MPIs into a single "enterprise person index" (EPI). Even more difficult is the task of establishing a means of identifying and linking patient records across all health care settings. Primary efforts to establish these linkages will depend on standardization across multiple MPI files, linkage protocols, data protection and patient consent. The nurse informatics specialist will be important to the planning, implementation, application and evaluation process necessary to the integration of health information records to support patient care.