Health informatics and health sciences librarianship are separate disciplines, although both embrace computers and information. This chapter provides a basic framework for health informatics, including definitions and history. Specific divisions of health informatics include bioinformatics, imaging, clinical informatics, and public health informatics; these are discussed as well as overarching issues of standards and vocabularies, information retrieval and automatic classification, education in informatics, and privacy, confidentiality, and security. The chapter ends with a brief look at the future of health informatics, a discussion of the overlap between health sciences librarianship and health informatics, and potential roles for health sciences librarians.