Demography is a science that studies the structure, evolution, and movements of populations in time and space. It is believed that having timely statistics and information about the population and its related characteristics is an essential tool for planners, policymakers, and researchers. In addition, the study of the time series of population indicators by gender and urban and rural areas is a beacon that illuminates the way for future studies. The book " Iran Demography " (comprising the first volume of population structure and distribution and the second volume of the link between population and development) is the first comprehensive book in the field of demographic studies in Iran with emphasis on demographic characteristics of Iran during the last half-century, which have been prepared, having an eye on the ever-increasing need of planners, researchers, and students, with the aim of introducing issues and demographic indicators and then analyzing demographic changes and developments in Iran. After stating the definitions and concepts for each index, if the necessary information was available in Iran to calculate the index, the relevant indicators were calculated and analyzed in a time series. In some cases, the indicators were calculated provincially and then analyzed. The main sources for calculating the indicators are the results of the general population and housing censuses from 1335 to 1390, various survey plans, and also register data. The book is the end result of many years of study, analysis, and expert experience of demographers of the Statistics Center of Iran, Ms. Elham Fathi and Mr. Noorollahi, which has been reviewed and finalized by providing opinions, advice, and correction of the great scientist and professor Dr. Habibollah Zanjani. The book " Iran Demography " consists of 24 chapters and deals with the topics of population size, sources and methods of producing demographic data in Iran, age structure and gender composition of the population, household and family, marriage and matrimony, fertility, mortality, migration, and population redistribution, population and Urbanization in Iran, Labor Force, Literacy and Literacy Level, Gender and Population Statistics, Sustainable Development and Population, Millennium Development and Population, Census Results Evaluation, Disability and Population Statistics, Housing and Population Statistics, Religious Characteristics of Population, Population Policies, Foresight, and population forecasting, the introduction of population software package programs and the position of the population in social and economic planning.