This paper considers the influence of labor demand for new PhD recipients on time to the doctorate. I use student-level data on all doctorates awarded by U.S. universities in seven humanities and social science fields together with the annual number of job listings by field from 1975 to 2005. An increase in the number of job listings in a field does not affect the completion probability contemporaneously but does increase it three to six years later. Time series variation in job listings by field can account for about 20 percent of the variation in average time to degree by entry year. Data Sources and Variable Definitions are appended. (Contains 3 figures, 7 tables and 13 footnotes.)