The 59th in a series of reports on national collegiate enrollments, this report includes statistics, interpretations, and trends in enrollment in four-year and related institutions for 1978-79. The institutions surveyed included four-year and upper division colleges, universities, and other baccalaureate degree-granting schools, graduate, professional, and theological schools; and those two-year collegiate-level institutions administered by the institutions in the above categories. Total enrollment for the year showed a decrease of .3 percent. The loss occurred primarily in public institutions. Total full-time student enrollment was down .9 percent for 1978-79 while part-time enrollment was up by 1 percent. When the results of this study are interrelated with those of two-year college studies, the reported grand total in all 2,588 collegiate-level responding institutions was 10,625,562. Enrollment projections are also discussed and a glossary of terms is provided. (SF)