HaRav Ostroff is an esteemed scholar and talmid of many of the Gedolim of our generation. During his many years of study at Yeshivat Kol Torah, he formed a close relationship with HaGaon HaRav Shlomo Zalman Auerbach zt"l, and was greatly influenced by him. He subsequently joined the kollel of HaRav Ezriel Auerbach, studying in the beis midrash of Ner Yisrael, and learning with him b'chavrusa over a period of 13 years. Subsequently, he spent several years of shimush in Hora'ah in the Beit Hora'ah of the great posek HaGaon HaRav Shmuel Vozner, Shlita, of Bnei Brak.
Rav Ostroff was appointed Moreh Hora'ah for a full range of designated Halachic matters by HaRav Moshe Sternbuch, shlita, under whose auspices he publishes a weekly bulletin on Hilchos Shabbos. HaRav Ostroff is a principal of Meor Bayis Yaakov in Jerusalem.