Avraham Haim Yosef (Avi) haCohen Weiss is an American Modern Orthodox ordained rabbi, author, teacher, lecturer, and activist who heads the Hebrew Institute of Riverdale in The Bronx, New York, from which he will be retiring in 2015. He is the founder of Yeshivat Chovevei Torah, a rabbinical seminary he refers to as "Open Orthodox", a term he coined to describe a form of Modern Orthodoxy, founder of Yeshivat Maharat for Orthodox women, co-founder of the International Rabbinical Fellowship, a Modern Orthodox rabbinical association founded as a liberal alternative to the Rabbinical Council of America, and founder of the grassroots organization Coalition for Jewish Concerns – Amcha.