The three classic works on American Judaism in the twentieth century appeared just after midcentury, all echoing the theme of Jews “fitting in” America and reflecting the rapid upward social mobility of American Jews. In American Judaism, Nathan Glazer noted the trend toward religious identification among Jews as a way to fit in as an ethnic group by using a religious framework. Even though America at midcentury was hostile to ethnicity, it was open to religiosity. In Conservative Judaism, Marshall Sklare observed that this most mainstream of the three movements differed from Orthodoxy in terms of decorum. While the core beliefs and practices of Conservative Judaism mirrored Orthodoxy, the former emphasized decorum in worship that was congruent with American religious life. In Jewish Identity on the Suburban Frontier, Sklare found that the Jews in the Midwestern suburb of Lakeville were ambivalent about Jewish particularism. The midcentury perspective tended to appreciate American Judaism in terms of assimilation. Adaptations to American life were most readily visible in religious behaviors. This perspective has continued to inform more recent studies such as Steven M. Cohen’s Jewish Identity and American Modernity, which used religious observance to gauge assimilation. Adaptations to American life were most readily visible in religious behaviors. This perspective has continued to inform more recent studies such as Steven M. Cohen’s Jewish Identity and American Modernity, which used religious observance to gauge assimilation. Beginning in the 1980s, American sociologists of religion introduced two new perspectives that have informed the understanding of contemporary American Judaism. In Habits of the Heart, Robert Bellah introduced the notion of religious privatization and the sovereignty of the individual in making religious decisions.