Chabad of the Upper East Side and the historic Park East Synagogue announced Friday a broad new partnership that will bring Chabad’s rabbinic leadership and a number of its growing programs into the 136-year-old congregation, marking a significant new chapter for Jewish life on the Upper East Side.

Beginning this Rosh Hashana, Rabbi Ben-Tzion Krasnianski, who has led Chabad of the Upper East Side for 35 years, will serve as Associate Rabbi of Park East Synagogue alongside its longtime Senior Rabbi, Rabbi Arthur Schneier. Rabbi Yosef Wilhelm, shliach to young professionals on the Upper East Side, will serve as Assistant Rabbi, with the wider team of Chabad shluchim complementing the synagogue’s existing leadership and programming.

The arrangement will also give a new home at Park East to a number of Chabad’s major Upper East Side initiatives, including its Young Professionals community, Friendship Circle, Young Families programming, Upper East Side Kollel and Chabad of Hunter College, along with additional educational and communal programs.

Park East Synagogue has served the Upper East Side for 136 years and has developed into one of Manhattan’s prominent traditional Jewish congregations. Rabbi Schneier, who has led the shul for more than six decades, is widely known for his work on behalf of Jewish communities and religious freedom around the world.

“For 136 years, Park East has stood as a beacon of Jewish faith, tradition, and community,” Rabbi Schneier and Park East president Les Lieberman wrote to congregants in announcing the partnership.

They described the move as building on Park East’s existing character while opening the congregation to expanded Jewish programming.

“Our goal is simple: to build upon the extraordinary foundation of Park East Synagogue while creating even more opportunities for Jewish life to flourish,” they wrote.

The partnership brings Chabad into the synagogue at a particularly significant point in the history of both institutions. Park East brings a large and longstanding congregation, a landmark shul and generations of Jewish life on the Upper East Side, while Chabad brings a network of shluchim and programs that has expanded steadily across the neighborhood over the past three and a half decades.

Rabbi Krasnianski and his wife, Chanie Krasnianski, arrived on the Upper East Side in the summer of 1991 as the Rebbe’s shluchim, with the goal of reaching Jews across the neighborhood regardless of background or level of observance.

“When we arrived on the Upper East Side, we dreamed of building a Jewish home where every Jew, regardless of background, affiliation, age, or level of observance, would feel welcomed, valued, and inspired,” Rabbi Krasnianski wrote Friday. “Today, that journey has taken a giant leap forward.”

What began with one couple has since grown into an extensive network of shluchim serving different segments of the Upper East Side.

Rabbi Boruch and Leah Jacobson established Chabad of Hunter College; Rabbi Uriel and Shevy Vigler built a Hebrew-speaking community and later founded B’Lev Echad; Rabbi Yosef and Devorah Wilhelm developed a large community for Jewish young professionals; Rabbi Shlomo and Sara Gutnick built Friendship Circle; Rabbi Sholly and Goldie Freundlich established Chabad Care, serving patients and families in area hospitals; Rabbi Moshe and Yocheved Krasnjansky lead programming for young families, including Hebrew School and camp; and Rabbi Yaakov Krasnianski works with the neighborhood’s senior community.

Chabad of the Upper East Side also operates the Schneerson Center for Jewish Life, which houses a mikvah, preschool, Kollel and adult education programs, alongside a range of neighborhood and online Torah initiatives.

Under the new partnership, the Park East campus will become an additional center for much of that activity, while the synagogue expects to expand its weekday and Shabbos programming, shiurim and lectures, programming for young professionals and families, and Yom Tov events.

Rabbi Krasnianski emphasized that the partnership is intended not simply as an arrangement between two organizations, but as a way of combining the reach and strengths they have developed over many decades.

“This is about far more than two institutions sharing a building,” he wrote. “It is the coming together of two great Jewish legacies with one shared mission: to strengthen Jewish identity and Jewish pride in every Jew on the Upper East Side.”

Rabbi Schneier and Lieberman similarly presented the partnership as an expansion of Park East’s longstanding mission.

“By working together, we will be able to expand the opportunities available to our members and create an even more dynamic and welcoming synagogue experience,” they wrote.

Rabbi Krasnianski also noted a personal historical connection between the two rabbinic leaders: Rabbi Schneier is a descendant of the Alter Rebbe and, over the years, consulted with the Rebbe on matters affecting Jewish communities around the world.

The shluchim estimate that some 70,000 Jews live across the Upper East Side, leaving a broad population still to be reached through classes, Shabbos meals, community programs and individual mitzvos.

“There are still thousands of Jews on the Upper East Side waiting for an invitation, a friendly overture, a class, a Shabbat meal, or a mitzvah that can change a life,” Rabbi Krasnianski wrote.

For Park East, the partnership opens its next chapter by bringing an expanding network of younger families, professionals, students and communal programs into the orbit of the historic congregation. For Chabad, it gives its growing network a major new base from which to reach Jews throughout the Upper East Side.

“At a time when Jewish people around the world seek strength, unity, and hope, we believe this collaboration reflects those very ideals,” Rabbi Schneier and Lieberman wrote. “By combining our strengths and working together, we can better serve our congregation, welcome new generations of Jewish families, and ensure that Park East Synagogue continues to thrive for many years to come.”