Synopsis Almost all the development activities of the world are badly affected (hampered) due to increasing rate of population which has not only challenged the very existence of natural resources but also restricted for the betterment of human beings. Obviously, the excessive population growth reduces per capita income, standard of living and creates a number of social tensions. No doubt, efforts have been made to solve various socio-ecodemographic problems, but because of the rising population the desired results are not being achieved. This needs the proper understanding about the size, structure and distribution of country's population and the formulation of suitable population policies. Consequently, it requires a thorough analysis of all the responsible or some of the factors, having a direct bearing on high population increase as well as a clear understanding of the population distribution. The latest innovation in this direction is the use of models for these phenomena. Based on the experiences of certain rural field studies, this book presents some deterministic as well as stochastic models for the pattern, determinants of migrations and its linkages with other socio-economic and demographic factors.