The purpose of this introductory manual is briefly to explain and put into context the elements involved in marine information center development and operation. Its goal is to provide an overview and create an awareness of the range of the inter-connected procedures, activities, and products that make up an information service. The introductory materials provided describe the process of making a document available to users and the functions of information centers and libraries. The remainder of the manual focuses on the various aspects of a marine information center: (1) Marine Information Center (e.g., descriptions of its planning and management, subject scope, the users, staffing, the collection, selection, acquisition, recording, cataloging, classification, arrangement, loans, interlibrary loans and document delivery, current awareness, indexing, information retrieval, translation, information products and publications, information and data analysis, referral, and disaster contingency planning); (2) Automation (databases, search procedures, compact disc systems, in-house systems, CSD/ISIS bibliographic software, database structures and standards, integrated systems); (3) International Information Systems (rationale and benefits); (4) The Aquatic Sciences and Fisheries Information System (ASFIS) ("Aquatic Sciences and Fisheries Abstracts"--ASFA, current awareness publications, registers and directories, ASFIS reference series, "World List of Aquatic Sciences and Fisheries Serial Titles," participation in ASFIS, and responsibilities and benefits); (5) The ASFIS Center (designation and duties); (6) Network Development, Cooperation, and Collaboration; (7) Promotion; and (8) Training. A 19-item list of references and a directory of selected ASFA/AFSIS centers, institutions, and agencies concerned with marine information exchange and database hosts offering online access to bibliographic databases conclude the manual. (MAB)