An automated dialer (100) for a call center (105) maximizes agent efficiency in two different ways. In a first method overdial probability is expressed as a probability function of number of agents and total traffic volume; the probability function is set equal to a maximum allowable overdial probability; and the resulting equation is solved for maximum total traffic volume producing the maximum overdial probability. The maximum total traffic volume is then used to determine a new dialing rate by dividing the difference between the calculated maximum traffic volume and known inbound traffic volume by the product of average call length and hit rate, where hit rate is the percentage of connected calls to total dialed outbound calls. In a second method a maximum total traffic volume is calculated from total number of agents times a desired agent utilization factor, and the total traffic volume is used as in the first method to calculate and set a new dialing rate for outbound calls.