The Series Completion service can be assigned to a selected series of lines to forward calls on a busy condition. It is a form of “hunting” in which the next line in the group is tried in a prearranged order, without any limit on the number of sequential forwards. This service is used to support Key System functionality. Key Systems typically ring all available lines in a specified order for incoming calls, regardless of the number dialed to reach the company. For example, when calling a technical support hotline, the incoming call attempts to ring line 1 of the company. If line 1 is busy, it will attempt to ring line 2. If line 2 is busy…and so on. If all the lines are busy, the call can be sent to Voice Messaging or another assigned service of the group. Similarly, if all lines or users of this company were assigned to a Series Completion group, BroadWorks acts just like a Key System.