This piece of work is targeting students both at undergraduate and Post-graduate levels, population scientist and other stakeholders who have research interest in the field of family demography and population policy related issues. Therefore, due to gradual changes in socio-economic, demographic and intermediate factors affecting family formation, the relevance of marriage in egalitarian societies has been questioned.Thus, this book unveils the contemporary issues that will inform policy makers on family revolution that has taken place overtime.Besides, current debates on family formation are raised and discussed in detail based on different theoretical underpinnings such as Bongaarts, Social disorganization, Second demographic transition and out-of wedlock models which are applied and tested empirically.