These notes are a transcript of lectures delivered by Oyvind Gron during the spring of 1997 at the University of Oslo. The present version of this document is an extended and corrected version of a set of Lecture Notes which were typesetted by S. Bard, Andreas O. Jaunsen, A Frode Hansen and Ragnvald J. Irgens using LT X2 . Svend E. Hjelmeland has made E many useful suggestions which have improved the text. I would also like to thank Jon Magne Leinaas and Sigbjorn Hervik for contributing with problems, and Gorm Krogh Johnsen for help with nishing the manuscript. I also want to thank prof. Finn Ravndal for inspiring lectures on general relativity. While we hope that these typeset notes are of bene t particularly to students of general relativity and look forward to their comments, we welcome all interested readers and accept all feedback with thanks. All comment may be sent to the author by e-mail.