Although the Aeronautical Information Exchange Model (AIXM) and ICAO Weather Information Exchange Model (IWXXM) standards are quite mature, the implementation of those standards is open to interpretation. Differences between International Air Navigation Service Providers' (ANSPs) implementations have been observed during the development phase of the Mini Global (MG) Phase II project. These differing interpretations in the implementation of AIXM and IWXXM standards could jeopardize interoperability. This paper focuses on the observed differences and the solutions developed for the MG II demonstration for AIXM and IWXXM interoperability between the United States, Asia, Caribbean, Europe, and Middle Eastern regions.