This book goes into the intricacies of the vimsottari and other nakshatra based planetery dasa (udu dasa) to bring out their need and usage. An independent chapter is devoted to the choice of dasa, the how and why of choosing the right dasa for a chart while considering the various criteria as well as variation options in a step by step approach. Judgement of dasa includes the principles, in general used for reading the message of the charts and in timing the events that the drama of life shall show.