This book provides analyses of sanitation, health, population dynamics and demographic variables from different perspectives, including data science, statistics, modeling, economics and natural sciences, to inform sustainable decision making and policies related public health and hygiene and in mainly rural and impoverished areas. The structure is arranged into three broad sections: Part I, Population Dynamics, Environment and Society; Part II, Health, Livelihood and Policy Response; and Part III, Water, Sanitation, and Hygiene (WASH). The book makes recommendations for policymakers on designing and delivering social protection policies to deal with different aspects of water, health, sanitation, population, and hygiene, taking the needs of women and rural communities into special consideration. It also aims to educate students and early career researchers, to help them develop novel approaches for sustainability with environmentally sound practices.