The author explores the economic and social consequences of Sri Lanka,s population changes in the last six and a half decades. It is then stated that the most important factor that has influenced and determined Sri Lanka,s development was the momentum and magnitude of the country,s population changes. The author then proceeds to highlight the various impacts of demographic changes on the economy through components such as the trade balance, public finances of the country and poverty. The phases of population growth and the ageing population are also introduced and highlighted in this book.