The first volume of correspondence contains the letters written by and to Karl Leonhard (and Sophie)Reinhold between 1773 and 1788. The correspondence from this period provides insight into Reinhold’s private life and makes it possible to reconstruct the first stages of his scholarly work as an advocate of Kantian philosophy. The correspondence with well-known figures such as I. von Born, Ch. M. Wieland and I. Kant) and less well-known figures gives a clear picture of Reinhold’s early years in Jena after his flight from Vienna in the fall of 1783. In addition it contains the philosopher’s personal data and information on his career in the Barnabite Order as well as in the masonic lodge »Zur wahren Eintracht«. The volume also includes a list of Reinhold’s published and unpublished writings (1777–1788), his reviews,(1782– 1788) as well as indexes of places, persons and subjects.