In 1970, the Carnegie Commission on Higher Education developed a classification of colleges and universities to support its internal program of research and policy analysis. Derived from empirical data on colleges and universities, the Carnegie Classification was first published for use by other researchers in 1973. For over three decades, the Carnegie Classification has since become the leading framework for describing institutional diversity in U.S. higher education. It has been widely used in the study of higher education, both as a way to represent and control for institutional differences, and also in the design of research studies to ensure adequate representation of sampled institutions, students, or faculty.

Updates to the classification occurred in 1976, 1987, 1994, 2000, 2005 and most recently in 2010. To ensure continuity of the classification framework and to allow comparison across years, the 2010 Classification update retains the same structure of six parallel classifications, initially adopted in 2005. They are as follows: Basic Classification (the traditional Carnegie Classification Framework), Undergraduate and Graduate Instructional Program classifications, Enrollment Profile and Undergraduate Profile classifications, and Size & Setting classification. These classifications provide different lenses through which to view U.S. colleges and universities, offering researchers greater analytic flexibility. These classifications were updated using the most recent national data available as of 2010, and collectively they depict the most current landscape of U.S. colleges and universities.

Each institution can now be described more comprehensively by its composite profile in the set of all Carnegie classifications. Across all classifications, the theoretical number of possible classificatory combinations far exceeds the number of US higher education institutions. The higher education landscape is thus "patchy," with certain combinations of Carnegie classifications represented by a number of institutions, and other combinations with no institutions at all. One practical consequence occurs in the process of peer selection-no other institution in the Carnegie database is an exact match for Bucknell's profile.