This book presents a comprehensive understanding of the demographic transition in Sri Lanka. Writings on this theme by various writers during different time periods have failed to combine all the three components of population change but mainly concentrated only on mortality and fertility transitions. Even in those descriptions, superior prominence has been given to explain the fertility transition. However, as discussed in this book, majority have examined post-transitional fertility differentials but failed to elucidate how Sri Lanka was able to commence its onset of the fertility transition even in the absence of modern family planning methods. This book has attempted to widen our knowledge on the demographic transition in Sri Lanka by explaining all three transitions with the use of existing theories.