Today, the process has become more centralized, with the conversion candidate having to convince a rabbi and the beth din of their sincerity, and there will usually be a considerable amount of study. They will then be tested and formally accepted, the convert is issued with a Shtar geirut ("Certificate of Conversion").[17] As the conversion process becomes more centralized there are only a limited number of permanent conversion courts that are 'acceptable' to the Chief Rabbinate of Israel.