Abstract: Calls may be distributed and load balancing maintained for a distributed automatic call distributor (ACD) system by simulating a central FIFO queue at the central routing point of the system. The simulated FIFO queue either requires that the number of calls in queue and the oldest call waiting time of calls at each automatic call distributor be periodically provided to the central routing point or event-based data be provided on each call answered in the system or not routed by the central routing point. Deviations from FIFO order of service recorded at the simulated FIFO queue may signal the need for requiring a call at another automatic call distributor. With additional information on agents available, the call removal rate may be estimated. Also, delay estimates may be updated based on comparing actual and estimated delays over time.