After his marriage, Perlow taught at Hebrew Theological College in Skokie, Illinois. He later moved back to Brooklyn and settled in Crown Heights, becoming a member of the administration of the mesivta of Yeshiva Rabbi Chaim Berlin. In 1969, he was appointed rosh yeshiva at the Breuer's yeshiva, Yeshiva Rabbi Samson Raphael Hirsch, in Washington Heights, New York, a position he held for 11 years. He also served as the Rav of Congregation Bais Yosef in that city. After the death of his father on September 4, 1976, Perlow began serving as Novominsker Rebbe. In 1980, he established the Novominsk Hasidic Center and founded his own yeshiva, Yeshivas Novominsk Kol Yehuda, named in memory of his uncle, Rabbi Yehuda Aryeh Perlow of Novominsk-Williamsburg, in Borough Park, Brooklyn.
Agudath Israel of America
Perlow became an active member of Agudath Israel of America from 1975, when he was one of the main speakers at the 7th Siyum HaShas in New York. He became a leader of the Torah Umesorah organization as well. In December 1998, Perlow was named president of Agudath Israel of America, succeeding Rabbi Moshe Sherer, who had died seven months earlier. With his appointment, the presidential and leadership duties held by Sherer were divided between Perlow, the new president, and a three-man executive. Perlow was also head of the organization's Moetzes Gedolei HaTorah. Perlow frequently spoke out on issues affecting the American Orthodox Jewish world, including Internet usage, child abuse, Holocaust denial, overpriced Jewish weddings, and U.S. politics. In 2015, Perlow shocked attendees at the 93rd annual Agudath Israel of America dinner by directly appealing to President Obama to reconsider the Iran deal. At the 73rd annual Agudah convention in 1995, Perlow urged dialogue with non-Orthodox Jews while at the same time "lashing out at what he described as the 'false ideology' of non-Orthodox Judaism." In June 1999, he wrote in The Jewish Observer in support of a rapprochement in the long-standing feud between the Haredi and Reform movements. At the May 2014 Agudath dinner, he stated that the Reform and Conservative movements "have disintegrated themselves, become oblivious, fallen into an abyss of intermarriage and assimilation", and branded another movement, Open Orthodoxy, as being "steeped in apikorsos ". While New York CityMayor Bill de Blasio was the next speaker at the dinner, he did not challenge Perlow's remarks, which cast aspersions on the affiliations of the non-Orthodox Jewish population of New York City.
Death
In March 2020, Perlow urged American Orthodox Jews to follow social distancing and other precautionary guidelines in response to the coronavirus outbreak, saying: "We cannot behave the way we did last week or two weeks ago. We're told that the halakha is that we must listen to doctors, whether it's about a sick person or Yom Kippur". He was soon after infected by COVID-19 and on April 7, 2020, died due to complications from the disease. He was 89. His funeral was held in a private ceremony. The eulogies and saying of Psalms were broadcast live over the telephone, in order to limit the spread of the virus.
Personal life
Perlow's first wife, Yehudis, was the daughter of Grand Rabbi Avrohom Eichenstein of Zidichov-Chicago. The couple had two sons and two daughters. In 2004, Perlow remarried to Miriam Landynski, his first wife's sister and widow of Rabbi Yaakov Zev Landynski.