Critical Messaging is the fastest and most reliable way of activating Emergency Responders to respond to time critical incidents whether they are full time or volunteer. Still the most common platform used worldwide is a 30+ year old technology called paging which can be over various protocols including POCSAG, Flex and 2 or 5 tone voice. The reason these technologies are still used is well proven and documented. Some of these reasons are: Messages are sent in real time (not store and forward like SMS), Network infrastructure is stand alone and not subject to flooding like public cell networks, you can send one message to many devices at once, infrastructure and user devices costs are low. The only pitfall with paging is that it is a one way technology so there is no way to know if a message is received and who is responding easily. We will look at what new and current technologies can be incorporated to achieve this outcome while still utilising the benefits of paging.