Rabbi Isaac Elchanan Theological Seminary

Rabbi Isaac Elchanan Theological Seminary (RIETS), or Yeshivas Rabbeinu Yitzchok Elchonon (Hebrew: ישיבת רבינו יצחק אלחנן‎‎), is the rabbinical seminary of Yeshiva University, located along Amsterdam Avenue in Washington Heights, New York. It is named after Rabbi Yitzchak Elchanan Spektor, who died the year it was founded, in 1896.

The RIETS semikhah program is a structured four year curriculum. The primary focus is on advanced Talmudic learning as well as developing a proficiency in deciding matters of classical and contemporary Jewish law or halakha. The majority of talmidim in the semikha program are also enrolled in the Katz Kollel which is led by the Rosh Kollel, Rabbi Hershel Schachter. There are a variety of required ancillary courses intended to train students for careers as practicing rabbis, in fields such as homiletics, pastoral counseling, and Jewish philosophy. There is an honors track within the general semikha program where students receive an extra stipend and are required to take additional supplemental courses.

Many RIETS students are also concurrently enrolled in a variety of other graduate degree granting programs, including those in law, education, academic Jewish studies, psychology, and the sciences.

RIETS has two post-semikha kollelim, referred to as the Kollel Elyon, which offer talmidim the opportunity to study Torah at an advanced level and take supplemental courses for an additional 3 to 4 years while receiving a generous stipend. The Roshei Kollel of the Kollel Elyon are Rabbi Michael Rosensweig and Rabbi Mordechai Willig.

Prior to the founding of Yeshiva College in 1928, RIETS, or Yeshivas Rabbeinu Yitzchok Elchonon (the institutional name in its Hebrew version, and as it appears on the seals of all affiliates of Yeshiva University) referred to both the Manhattan Talmudical Academy (which merged with the Brooklyn campus to form the present-day Marsha Stern Talmudical Academy) and the post-High School yeshiva and semicha program. Historically, the head of Yeshiva University served in a dual capacity as both president of Yeshiva University as an academic institution and also as the rosh yeshiva ("dean") of RIETS. RIETS and Yeshiva University were a single entity for most of the first half of the twentieth century. However, their second president, Rabbi Samuel Belkin, legally separated the two institutions in order to obtain United States government funding and research grants for a variety of YU's secular departments. In Rabbi Belkin's view, the modern understanding of the separation of church and state in the United States would have otherwise forced YU to either forgo federal grants (a major source of funding for all universities) and stagnate, or alternatively to unacceptably alter the religious character of RIETS. The split was strongly opposed by RIETS's leading scholar Rabbi Joseph B. Soloveitchik, who saw it as the antithesis of Yeshiva University's guiding philosophy. Rabbi Belkin prevailed and, following the split, he remained both the official rosh yeshiva of RIETS and president of Yeshiva University. Nevertheless, the undergraduate Talmud department of Yeshiva College is also referred to as Yeshivat Rabbeinu Yitzchak Elchanan, is administered by the same dean, is taught by the RIETS Roshei Yeshiva, and most of its shiurim are populated by both undergraduate and graduate students without any distinctions. MTA, now also called Yeshiva University High School for Boys, while under a different administration and taught by a separate faculty, is referred to as the Mesivta of Yeshivas Rabbeinu Yitzchok Elchonon.