In recent years, an increasing number of direct marketers are turning to private prospect databases as a means to combat the external forces that spoil their customer acquisition efforts. For marketers who use direct mail to acquire customers, challenges include declining response rates, list fatigue, lack of new names, shortened campaign times, and the need for timely postcampaign metrics. Not too long in our past, we could have dialed up our modeling efforts, but even sophisticated modeling techniques have their limitations against these industry forces.