The following thesis is written in five parts. These include a diversity paper, a zoogeography paper, two taxonomy papers, and a catalogue. Although each paper is a separate entity, they are all inherently related. The foundation of the thesis is a series of collections made between southern New Zealand and McMurdo Sound, Antarctica, intermittently from December 1970 to February 1973. They have formed the basis of the diversity study and raised the questions on which the rest of the thesis depends. Sorting, identifying and counting the animals in the collections has been a long slow job, broken up by other shorter studies presented here and elsewhere. The zoogeography study was undertaken to gain a better understanding of the origin and present day distribution of Antarctic Amphipoda and Polychaeta, the two main groups in the diversity study. Much of this work consisted of searching the literature and compiling distribution records which were sorted by the computer into areal checklists. The mechanics for this line of research are now worked out and I hope to continue it for other Antarctic invertebrate groups with the objective of looking for large scale zoogeographic trends. As the zoogeography study progressed it became apparent that the literature on Southern Ocean amphipods was badly in need of unification. Since I had most of the literature at my fingertips, and since I had to determine synonymies and distributions for the zoogeography study I decided to formalize this information into a catalogue, which was subsequently done with the help of Miss Suzanne Bullock. The catalogue was compiled on a computer and is very easy to update as new information becomes available. This makes it a continuous record of published information on Southern Ocean Amphipoda. The two amphipod taxonomy papers came directly from the collections for the diversity study. Unfortunately they describe only a small proportion of the new species in the collections. I anticipate describing more of these species at a later date, along with other new amphipod species collected by Dr Horning and me, particularly in the New Zealand Subantarctic. As for the other kinds of invertebrates in the collections, some are already being studied by specialists or have been given to museums, and this is the eventual fate of the entire collection.