Earning your doctoral degree is a big commitment, but it can offer big rewards, too. Not only do a number of careers simply require applicants to hold doctoral degrees, but those who have invested in these advanced degrees can expect to earn more than those with bachelor's or master's degrees alone. According to the U.S. Census Bureau, doctoral degree holders earn an average of $3.4 million during the course of their working lives, while those with bachelor's degrees can expect to earn an average of $2.1 million. Choose a school to get started.