This study examines command, control, communications, computer, and intelligence (C4I) systems interoperability progress within the United States (U.S.) military services and amongst coalition partners since the year 2000. This study uses national military strategy, joint military strategy, service unique strategy and doctrine, Joint Tactical Radio System (JTRS) and Defense Integrated Military Human Resource System (DIMHRS) case studies, Defense Information Systems Agency (DISA) technological standards, C4I technical reports to establish trends, patterns, and gaps in coalition interoperability. C4I interoperability successes are abundant since 2000 but it is clear from current day operations and research that the U.S., its allies and coalition partners need further improvements in order to master the many moving parts required for true coalition C4I systems interoperability. Clearly, acquisition, development, testing, and fielding must be fully integrated into either a joint or coalition solution. In order to achieve C4I interoperability, this study recommends changes in law, namely to the Goldwater-Nichols Act of 1986 to further define the strategic intent of system interoperability among services of the DoD and foreign nations. Changes to national military strategy, joint military strategy, and service-unique military strategy are required to overhaul and emphasize the unequivocal need for fully interoperable C4I systems across the DoD and amongst coalition members. Acquisition, although not fully explored within this study, requires a greater emphasis in order to speed delivery of these interoperable systems to the field. Development and testing mechanisms exist throughout industry and within the military services to ensure interoperability but again, speed requires greater emphasis to ensure the technological advancements meet the soldier, sailor, airman, and marine before they become obsolete.
