Acknowledgements

First and foremost I would like to thank my thesis advisor Inger Jørgensen, who has shown a large and consistent interest in my project during the times. Our numerous scientific discussions and her many constructive comments have greatly improved this work. She is also thanked for letting me use her Coma data not yet published (Jørgensen 1997b, in prep.).

Part of the thesis work was done while I was visiting scholar at The University of Texas at Austin. It is a pleasure to thank the Astronomy Department and McDonald Observatory for their hospitality. I am also indebted to the many people in Austin in and outside the Astronomy Department who made my stay in Austin a very pleasant one. The Fulbright Commission and Observator Julie Marie Vinter Hansens Rejselegat are acknowledged for their kind financial assistance, which in part funded my stay in Austin.

It has been a pleasure to study at the Observatory in Copenhagen during the years. My fellow students are cordially thanked for their friendship. Also my friends and family outside astronomy are thanked for their good company and support.

Lars Lindberg Christensen and Sune Hermit are thanked for helpful comments on the manuscript.

Leif Hansen, Henning Jørgensen, and Per Kjærgaard are acknowledged for their help in obtaining funding for my participation in the ESO/VLT workshop on Galaxy Scaling Relations in Garching, November 1996. Leif is also thanked for various assistance during my thesis work.

Last but not least I would like to acknowledge Åke Nordlund for his large responsibility for the outstanding computer facilities we have in Copenhagen, and for his stimulating courses on computer related topics.