In April 1992, Tom Lopez, then a certified public accountant in California, started thinking about switching careers. "I decided that the thing I really wanted to do was teach at the college level," he said. And that would mean earning a Ph.D. in accounting. But Lopez, who is now an associate professor of accounting at the Moore School of Business, University of South Carolina, had a wife and three young children at the time. How could he possibly afford to quit his job and go back to school?