- Undergraduate students of sound character in any department of a college or university having an institutional chapter who have been registered in the institution for at least one year.
- In their junior year, rank scholastically in the upper 7 1/2 percent of the class, after completing at least one term with junior standing.
- In their senior year, rank in the upper 10 percent of the class at the time of nomination.
- Eligibility may be determined separately for each academic unit within a member institution.
- Graduate and professional students of sound character who are candidates for an advanced degree in any college or university having an institutional chapter, have made an outstanding record in graduate and professional study as evidenced by ranking scholastically in the upper 10 percent of all graduate and professional students in that institution, and had an outstanding undergraduate record as evaluated by the chapter selection committee.
- Chapters may also induct a limited number of faculty and honorary members.