Once again this report consists of detailed discussions of a limited number of topics of current interest, which have not been discussed in recent reports. The subjects are: Mixing in Stellar Evolution (A. Maeder); Supernovae (J. Craig Wheeler); Theory of Variable Stars (J. Cox); Theoretical Studies of Star Formation (J. J. Monaghan); The Age and Helium Content of Globular Clusters (V. Castellani). Because the first three contributions have been written by different authors there is a small amount of overlap in their contents. I am very grateful to the authors for providing their reports very promptly. The references are in general identified by their number in Astronomy and Astrophysics Abstracts but many references are too recent for this to be possible and a few others were not included in A & A Abstracts.