Professional fraternities, in the North American fraternity system, are organizations whose membership is restricted to students and faculty members in a particular field of professional education. Within that field, their membership is exclusive; however, they may initiate members who belong to other types of fraternities.
Professional fraternities are often confused with honor societies because of their focus on a specific disciple. Professional fraternities are actually significantly different from honor societies in that honor societies are associations designed to provide recognition of the past achievement of those who are invited to membership. Honor society membership, in most cases, requires no period of pledging, and new members can be immediately inducted into membership after meeting predetermined academic criteria and paying a one time membership fee. Because of their purpose of recognition, most honor societies will have much higher academic achievement requirements for membership. Professional fraternities, on the other hand, work to build brotherhood among members and cultivate the strengths of members in order to serve the community and provide assistance to one another in their mutual areas of professional study. Membership in a professional fraternity is generally the result of lengthy pledge process, much like any other social fraternity; and members are expected to remain loyal and active in the organization for life. A few groups, such as Phi Sigma Pi, are considered to be both a fraternity and an honors organization. These organizations require higher GPAs, like an honor society, but operate as a brotherhood like a traditional professional fraternity.

History
While nearly all professional fraternities are now required by federal law (commonly referred to as "Title IX," enacted in 1972) to be co-ed, several still restrict membership to only men or only women. Because the primary goal of professional fraternities is to prepare students to be leaders in specific professions, and to advance the interests of those professions, under Title IX, it would be considered discrimination to limit such opportunities to one sex, and federal funding could be withheld from any institution that discriminates on the basis of sex. The few professional fraternities that have remained single sex have been allowed to do so because they have defined themselves primarily as general social fraternities, while still retaining their focus on a specific professional discipline. Department of Education regulations adopted pursuant to Title IX allow such an exception for "the membership practices of social fraternities and sororities." (34 C.F.R. Sec. 106.14(a)). Examples of professional groups that have been granted exception to remain single sex because of their social focus include Alpha Gamma Rho, Phi Mu Alpha Sinfonia, and Sigma Alpha Iota.

Title IX Applied to Professional Fraternities
Most major professional fraternities are members of the Professional Fraternity Association. This group resulted in 1978 from a merger of the Professional Interfraternity Conference (PIC) (for men's groups) and the Professional Panhellenic Association (PPA) (for women's groups).

Umbrella Organizations

List of professional fraternities

ΑΖ - Alpha Zeta - Agriculture
ΑΓΡ - Alpha Gamma Rho - Agriculture, exclusively male
ΣΑ - Sigma Alpha - Agriculture, exclusively female Agriculture

ΑΡΧ - Alpha Rho Chi - Architecture
Scarab - Architecture Architecture

ΑΚΨ - Alpha Kappa Psi - Business
ΓΙΣ - Gamma Iota Sigma - Insurance, Risk Management, Actuary Science
ΔΣΠ - Delta Sigma Pi - Business
ΠΣΕ - Pi Sigma Epsilon - Sales and Marketing
ΡΕ - Rho Epsilon - Real Estate
ΣΙΕ - Sigma Iota Epsilon- National Honorary and Professional Management Fraternity
ΦΓΝ - Phi Gamma Nu - Business
ΦΧΘ - Phi Chi Theta - Business Engineering

ΔΘΦ - Delta Theta Phi - Law
ΦΑΔ - Phi Alpha Delta — Law
ΦΔΦ - Phi Delta Phi - Law Law

AΓK - Alpha Gamma Kappa - Podiatry
ΑΤΔ - Alpha Tau Delta - Nursing
ΑΩ - Alpha Omega - Dentistry
BΣ - Beta Sigma - Medicine
ΔΕΜ - Delta Epsilon Mu - Health
ΔΣΔ - Delta Sigma Delta - Dentistry
ΚΓΔ - Kappa Gamma Delta - Medicine
ΚΕ - Kappa Epsilon - Pharmacy
KTE - Kappa Tau Epsilon - Podiatry
ΚΨ - Kappa Psi - Pharmacy
ΜΣΦ - Mu Sigma Phi - University of the Philippines Medicine
ΣΜΔ - Sigma Mu Delta - Medicine
ΣфХ -Sigma Phi Chi- Chiropractic womens professional sorority
ΦΑΣ - Phi Alpha Sigma - Medicine
ΦΔΕ - Phi Delta Epsilon - Medicine
ΦΔΧ - Phi Delta Chi - Pharmacy
ΦKM - Phi Kappa Mu - Medicine - University of the Philippines
ΦΡΣ - Phi Rho Sigma - Medicine
ΦΧ - Phi Chi - Medicine
ΩΤΣ - Omega Tau Sigma - Veterinary Medicine Medicine

ΔΟΣ - Delta Omicron Sigma - Military veterans
ΔΦΕ - Delta Phi Epsilon - Foreign Service
Scabbard and Blade - Military Military, Government, & Foreign Service

ΔΟ - Delta Omicron - Music
ΚΚΨ - Kappa Kappa Psi - Band
ΜΦΕ - Mu Phi Epsilon - Music
ΣΑΙ - Sigma Alpha Iota - Music, exclusively female
ΤΒΣ - Tau Beta Sigma - Band Service

ΑEΖ - Alpha Epsilon Zeta - South Asian Professional
ΑΕΡ - Alpha Epsilon Rho - Broadcasting
ΑΗΡ - Alpha Eta Rho - Aviation
ΑΧΣ - Alpha Chi Sigma - Chemistry
ΓΕΤ - Gamma Epsilon Tau - Printing and Digital Media
ΖΦΗ - Zeta Phi Eta - Communication arts & sciences
ΛΑ - Lambda Alpha - Anthropology
ΛΚΣ - Lambda Kappa Sigma - Pharmacology for women
ΡΠΦ - Rho Pi Phi - Pharmacology
ΦΑΤ - Phi Alpha Tau - Communicative Arts
ΦΒ - Phi Beta - Creative and Performing Arts
ΦΣΠ - Phi Sigma Pi - National Honor Fraternity