The controversial appointment of a new administrative head to the state's Conversion Authority Wednesday is expected to hamper efforts to encourage tens of thousands of non-Jewish Israelis to embrace Judaism. Muli Yeselson, an employee of the Joint Institute for Jewish Studies, which employs Orthodox, Conservative and Reform teachers who educate potential converts before conversion, was chosen by the Prime Minister's Office and the Civil Servants' Commission. However, various sources connected with the conversion authority expected Yeselson's appointment to further exacerbate already charged and complicated relations among groups within the authority. "I believe that Yeselson will not bring about a change," said outgoing administrative head Rabbi Moshe Klein. "Unless he succeeds in removing from the authority elements that are destroying the system, nothing will change in the world of conversions. For their own good, I call on all Israelis considering conversion not to begin the process. Under the current situation, they will never finish." Criticism of Yeselson's appointment was registered across the board. A source in the Immigration and Absorption Ministry said that Yeselson was on bad terms with many of the conversion court judges and lacked the necessary managerial experience to serve as administrative head. "This is a sad day for the conversion authority," said the source. "Apparently interests other than the improvement of the authority were at play." Rabbi Yitzhak Peretz, an aide to Chief Sephardi Rabbi Shlomo Amar, said that Yeselson was potentially problematic since he was coming from the Joint Institute, where non-Orthodox streams of Judaism are taught. "We have to wait and see whether he accepts Rabbi Amar as his new boss," he said. A source in the Conversion Authority said that even if Amar wanted to work with Yeselson, he would be unable to bear the criticism of the haredi rabbinical establishment. "Rabbi Amar will be blackballed if he cooperates with Yeselson," the source said. In contrast, Prof. Binyamin Ish-Shalom, head of the Joint Institute, said that Yeselson had extensive managerial experience. "He is responsible for liaisons between the institute and the conversion courts," said Ish-Shalom. "Yeselson is also responsible for about 3,000 classrooms around the nation and for maintaining contact with the adopting families of the potential converts. He has worked for us for the past decade, first as an educator and in various managerial positions. He has a degree in management." Ish-Shalom also praised Yeselson's moral qualities, saying, "Yeselson is a fair and honest man with many positive attributes. I wish him all the success in the world."