Data on summer and fall 1981 enrollments in Pennsylvania colleges and universities are presented, including a brief narrative section on trends. Detailed statistical tables cover the following: enrollments by enrollment status and by sex, fall 1972-1981; total enrollments by type of institution, fall 1972-1981; enrollments by level of study, fall 1972-1981; summer school registrations, 1972-1981; total enrollments by institution, fall 1972-1981; undergraduate enrollments by sex and enrollment status by institution, fall 1981; first-professional enrollments by sex and enrollment status by institution, fall 1981; graduate enrollments by sex and enrollment status by institution, fall 1981; unclassified enrollments by sex and enrollment status by institution, fall 1981; first-time freshmen enrollments by sex and enrollment status by institution, fall 1981; registrations by level of study by institution, summer 1981; and full-time-equivalent enrollments by level of study by institution, summer 1981. Trends include the following: with the exception of 1978, total enrollments in higher education have continued to rise over the last 10 years; both full- and part-time enrollments have increased; during the last 10 years, the number of female students enrolling in Pennsylvania colleges and universities has risen by 46.2 percent; in 1981 the percentage of females of the total enrollment was 50.8 percent; projections indicate a migration of students away from private institutions and toward the public institutions during the next 10 years; summer registrations have fluctuated considerably over the last 10 years; and undergraduate enrollments are the driving force behind the total enrollment in higher education in Pennsylvania. (SW)