He pursued graduate work at The Hague Academy of International Law and was admitted to the New Jersey bar in 1951.

[3] Guarini was elected as a Democrat for New Jersey's 14th Congressional District to the 96th United States Congress and was reelected six times.

[4] The Jersey City post office building on the corner of Montgomery and Washington has been dedicated to Guarini.

Dartmouth has created the Frank J. Guarini Institute for International Education in recognition of his longtime support of the college.

[5] In 2018, Dartmouth further recognized him by announcing the naming of the Guarini School of Graduate and Advanced Studies in his honor.