The minor field requirement ensures the correlation of knowledge and methods of inquiry from two fields related to but outside of the major field (the area of concentration). Minors should be selected to broaden the candidate's knowledge, expand methodological skills, and provide new insights for the major field of study.

Each minor is supervised by a faculty member conducting research or practice in that field. Normally a program of three courses of greatest value to the student is worked out and an examination or paper is submitted to establish proficiency. The plan agreed upon by the student and the supervising faculty member must be approved by the Ph.D. Committee. A relevant master's degree in a department other than architecture may be offered as sufficient evidence of proficiency for one minor.

One of the minor fields may be chosen within Architecture, but in a study area other than the major. This field is expected to contribute to breadth of understanding of architectural principles on the part of the candidate and may also contribute to the research underlying the dissertation.

In the table below are some examples of minors outside the Department of Architecture.