Call queues are used to route calls in a first-in/first-out manner to the appropriate agent. These agents can be logged into the system via an extension. Call Queues are commonly used with an ACD, where the callers hear an announcement similar to “thank you for calling, all available agents are busy, please hold for the next available agent, or press 0 to leave a message”. When an agent becomes available the call is routed to that agent. There are several routing options for call queues including: ring all, round-robin, least recent, fewest calls and random. These routing options ensure you fairly distribute calls across all agents in a queue. Automatic Call Distribution (ACD) is used to route calls in a call center environment to the appropriate agents, based on factors such as time availability, behavior, and priority levels.