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@@ -5,8 +5,13 @@ A node.js module to control [Samsungs SmartThings' Smart Home Monitor](https://s
 
 **This library requires that SHM is accessible to Home Assistant via MQTT, as discussed [here](https://ethitter.com/2016/08/smartthings-smart-home-monitor-shm-mqtt-home-assistant/).**
 
+Regardless of how many buttons are configured, only one SHM instance is controlled by any and all. I'm not sure why or how you'd have multiple SHM instances in a home anyway.
+
+**For security reasons**, the button will only toggle between the states that apply when people are home. This button is _not_ meant to turn on the alarm on the way out the door; that still requires the Home Assistant UI or the SmartThings app. Accordingly, **when the system is "armed away," the button won't have any effect.**
+
 ## Prerequisties
 
+* At least one Dash button (multiple are supported, but see above notes)
 * [Home Assistant](https://home-assistant.io/)
 * [SmartThings MQTT Bridge](https://github.com/stjohnjohnson/smartthings-mqtt-bridge)
 * [SmartThings SHM MQTT Bridge](https://ethitter.com/2016/08/smartthings-smart-home-monitor-shm-mqtt-home-assistant/)