In the late twentieth century in North America, an unprecedented rise in the level of intermarriage and conversion to Judaism occurred. This monograph begins by discussing the development of halakhah (Jewish Law) regarding conversion in early and medieval rabbinic sources, and the historical and sociological trends in the Jewish community leading up to this period. Based on this background, responsa by Modern Orthodox, Reform, Ultra Orthodox and Conservative rabbis are examined. Comparisons and conclusions are made based on how the rabbis read and analyze legal and extralegal texts, apply principles and incorporate their ideologies into their decisions. Ultimately, this research seeks to understand how halakhah and halakhic decisors respond to new situations while often reading the same core texts in fascinating and diverse manners.