Over the last generation, the instructional staffing system in U.S. higher education has experienced a significant reduction in the proportion of jobs for full-time tenured and tenure-track faculty members and a dramatic growth in "contingent" instructors--full-time non tenure track, part-time/adjunct faculty and graduate employees. About 70 percent of the people teaching in U.S. colleges today hold these temporary jobs, which lack tenure or a chance to become tenured. A recent study commissioned by the American Federation of Teachers and conducted by JBL Associates found that contingent faculty members now teach approximately half of all undergraduate public college courses in the United States. Contingent faculty members comprise an important component of the teaching force. They often bring unique experience and specialized knowledge to the classroom. Contingent faculty members, however, are not compensated proportionately for their contributions, and typically receive low pay and inadequate employment benefits, such as pensions and health insurance. While the growing reliance on contingent faculty is well established nationally, little detailed information exists on higher education staffing in particular states and individual higher education institutions. To begin addressing the lack of state-level data, this report extends recent research on higher education staffing trends to public institutions in one state--Pennsylvania. The report describes how Pennsylvania's public colleges and universities employ and compensate full- and part-time/adjunct faculty members and graduate employees to teach undergraduate courses. It documents Pennsylvania's system-wide reliance on contingent instructors and the disproportionately low salaries associated with part-time instructional employment. Appended are: (1) Keystone PA Higher Education Survey; (2) Data Source by Institution. (Contains 11 tables, 3 figures, and 18 footnotes.)