"Information" is a word that is much used and discussed, but with little agreement on its meaning. Yet information forms the professional focus and intellectual content of numerous disciplines and professions---information science, knowledge management, social studies of information, digital humanities, biomedical informatics, library science, archival science, records management, information systems, and many more. In this collection of eighteen professional papers and other texts by Professor Marcia Bates, of UCLA's Department of Information Studies, this pivotal concept is addressed in depth, and its relation to the information professions developed and discussed. A number of professional and disciplinary issues are considered, including definitions of the fields, research paradigms and methodologies, the role of the doctorate in a profession, and the major research content areas of the several fields, with special attention to information science. Finally, the distinctive experience of being a woman graduate student and professor, when that was still rare in American universities, is described. Bates' popular articles, "The Invisible Substrate of Information Science," "Fundamental Forms of Information," "The Information Professions: Knowledge, Memory, Heritage," An Introduction to Metatheories, Theories, and Models," and "Many Paths to Theory: The Creative Process in the Information Sciences" are included, among others. This is Volume I of three containing selected works by Bates. The others are titled: Information Searching Theory and Practice (Vol. II), and Information Users and Information System Design (Vol. III).