Butler is an automation tool within Trello that allows users to automate workflows easily. With Butler, users can automate a set of actions in Trello using triggers that are rule-based, via a simple click of a button, or through scheduled commands based on due dates or regular intervals. Butler can be further extended by adding the Butler app for Slack, bringing the power of automation from Trello into Slack channels. This allows users to send messages to Slack channels or colleagues when a new Trello card is added to a list or when a card is due, among other things.