Stellar evolution, mass loss and nucleosynthesis on the asymptotic giant branch

Problems relating to the evolution of stars on the asymptotic giant branch (AGB) are examined. Theoretical studies have been made possible by the use of computers to study AGB evolution, and a better understanding of these phenomena is due to better observational input such as the study of carbon stars and long period variables in the Magellanic Clouds and UV observations of planetary nebulae. Particular attention is given to the study of AGB mass loss (approximately 40% stellar wind mass loss, 40% supernova ejects, and 20% planetary nebulae) as well as nucleosynthesis in AGB stars, with significant contributions to the enrichment of the galactic interstellar medium made by these stars. These details are necessary to formulate galactic nucleosynthetic models, but it must be noted that they are still highly uncertain.