This chapter discusses that chemist of new group of alkaloids firmly roots ergot alkaloids in the well-cultivated soil of alkaloid research. In the history and development of research on ergot alkaloids, this decade is particularly important because much of the isolation and structure proposals of new components had been achieved during this period. Conversions of natural ergot alkaloids had been extensively carried out to establish the structures of newly isolated alkaloids by intercorrelation. Therefore, interest has been directed toward supplying less abundant components from the more abundant alkaloids, thus aiding relay synthesis in addition to total synthetic works. The ergoline skeleton is the most common structure of many ergot alkaloids. Therefore, from the beginning of synthetic work on these alkaloids, through studies on mutual conversions of ergot alkaloids had been regarded as a very important and key step not only for facilitating total synthesis of many alkaloids but also for utilizing natural sources as supply reserves. Lysergic acid was first isolated from hydrolytic solutions of ergot peptide alkaloids. From the fact that its derivatives, particularly amides, occur in nature as peptide alkaloids and show remarkable pharmacological activities lysergic acid itself has been regarded as the center of interest of not only medicinal chemistry but also synthetic chemistry. © 1990 Academic Press Inc.