This book examines the fundamentals of Jewish demography and sociology around the world. It is not only concerned with documenting patterns of population change but also with an intriguing and ever-present issue like "Who is a Jew?" The latter transcends the limits of quantitative assessment and deeply delves into the nature, boundaries, and quality of group identification. A growing challenge is how to bridge between concept related to ideals and theory and reality reflecting field research. Divided into six sections, the book discusses historical demography, immigration and settlement, population dynamics, social stratification and economy, family and Jewish identity in the U.S., and Jewish identity in Israel. The volume represents the dynamic and diverse nature of the study of world and local Jewish populations. It shows how that field of study provides an important contribution to the broader and now rapidly expanding study of religious and ethnic groups. Scholarsin disciplines such as history, geography, sociology, economics, political science, and especially demography follow and analyze the social and cultural patterns of Jews in different places around the globe, at various times, and from complementary perspectives. They make use of historical sources that have recently become accessible, utilize new censuses and surveys, and adopt advanced analytical methods. While some of their observations attest to consistency in the Jews demographic and identificational patterns, others evolve and ramify in new directions that reflect general processes in the areas and societies that Jews inhabit, internal changes within Jewish communities, and intergenerational trends in personal preferences of religious and ethnic orientations. This volume brings together contributions from scholars around the world and presents new and updated research and insights.