There are many types of exercises and drills. Authorities can choose to exercise parts of the response, or simulate an entire end-to-end warning and evacuation scenario. Similarly, exercises can be conducted only within departments or organizations, or involve entire communities, states, provinces, a country, a region (many countries comprising an entire ocean basin) or be convened internationally.  Finally, exercises can be conducted as simply orientation workshops that inform on what to expect, as slow discussion simulations between responders, or as fully involved, real-time exercises.