A call-distribution function (150) of an ACD system (101) improves the equity of distribution of calls to agents (106-108) by basing the distribution on the agents' individual occupancies. Illustratively, determining an agent's occupancy involves either determining (304) how many calls the agent has handled within a predetermined time interval, or determining (305) how much time of a predetermined time interval the agent has spent on handling of calls. The occupancy is periodically re-determined, and a next call is allocated to the presently least-occupied one of agents who are available to take the call, or to an agent to whose occupancy the allocation will be most beneficial, such as an available agent to whom allocation of the call will maximize convergence of actual and target occupancies. A queue (135) of agents available is ordered in the inverse order of the agent's occupancies, and a newly-available agent is slotted (inserted) (306) into the queue in a position (202) that ensures the continued inverse ordering of the agent queue. The occupancies of agents are then re-determined (308) and the agents are re-enqueued (310) accordingly.