Everyday, people in organizations must solve their problems to get their work accomplished. To do so, they often must find others with knowledge and information. Systems that assist users with finding such expertise are increasingly interesting to organizations and scientific communities. But, as we begin to design and construct such systems, it is important to determine what we are attempting to augment. Accordingly, we conducted a five-month field study of a medium-sized software firm. We found the participants use complex, iterative behaviors to minimize the number of possible expertise sources, while at the same time, provide a high possibility of garnering the necessary expertise. We briefly consider the design implications of the identification, selection, and escalation behaviors found during our field study.