Students complete a dissertation during their fourth and fifth years. The dissertation committee chairperson must be a member of the I.R.H.R. graduate faculty, and the committee must include at least three other faculty members. At least one committee member must be from outside the I.R.H.R. graduate faculty. All students present and defend their dissertation proposals in a seminar format. The proposal defense is open to all interested faculty members and Ph.D. students, although only the committee members vote on the acceptability of the proposal. A final oral defense takes place upon completion of the dissertation. It also is open to interested faculty and Ph.D. students.