Situating their argument in the context of the Western world’s 500-year history of marriage, the authors of this work reveal what factors encourage marriage and cohabitation in a contemporary society where marriage and the relationships between women and men have changed dramatically. While many people still choose to marry without first cohabiting, others elect to cohabit with varying degrees of commitment or intentions of eventual marriage. The authors’ controversial findings suggest that family history, religious affiliation, values, projected education, lifetime earnings, and career aspirations all tip the scales in favor of either cohabitation or marriage. This book lends new insight into young adult relationship patterns and will be of interest to sociologists, historians, and demographers alike.