Three ancient works, viz. the Carakasamhita, the Susrutasamhita and the Astangahrdaya are considered to be the three basic and authoritative works of the Ayurvedic tradition. Their respective authors, Caraka, Susruta and Vagbhata are, therefore, haloed names in the field of Indic medicine. They flourished n hoary past, a few centuries prior to the Christian era and their works have since been reorganized, edited and redacted, several times, by their successors in tradition, keeping pace with the progress of the science of healing. Some of those later authorities were conferred the titles of `Caraka', `Sugruta' and Vagbhata' in recognition of their contribution to the development of the text they worked with. This state of affairs has made it extremely difficult to reconstruct the biographical details and to ascertain the dates of the ancient authors who originally wrote these treatises. The Ayurvedic literature is vast and has an uninterrupted continuity of at least two thousand five hundred years. Innumerable classical and medieval authors contributed to its development. A complete survey of the literature which may help to trace the development of the science on the one hand and the influence and indebtedness of the successive authors on the other was, therefore, a desideratum. The present work Vrddhatrayi, written in lucid and idiomatic Sanskrit by the great savant Sri Gurupada Sarma Haldar fulfilled this desideratum. The main emphasis of the survey is on the identification, biography and age of the three ancient authorities, viz. Caraka, Susruta and Vagbhata, but at the same time it aims at the reconstruction of the biographies of their junior name-sakes and other Ayurvedic authors who have been mentioned in these texts either as predecessors or redactors. It also presents connected accounts of the life and works of many commentators and writers of compendia on Ayurveda. The author who was a versatile scholar in quite a few branches of Sanskrit learning has substantiated his conclusions with copious extracts from a vast range of text. The views of other writers on the subject and historians have been weighed and considered with due attention. The work has been made more useful by the addition of several indexes.