From their largely descriptive beginnings about a half century ago, studies on the ecology of small mammals have mushroomed in number, scope, content and complexity. Yet strangely, or perhaps not so strangely if one considers the extent and complexity of ecological interactions, the main problems for which the early workers sought answers still defy complete analysis, and basic hypotheses remain untested if not even untestable. The same holds true for so many branches of animal ecology that it seems to be the complexity of the concepts that frustrates efforts rather than the subject species. Like all branches of science, small mammal ecology has been subject to a series of fashionable approaches, one following another as tech nology penetrates previously impregnable regions. Doubtless the future development of our science will be punctuated by wave upon wave of new endeavour in whole fields that are perhaps even yet unidentified. Answers to the complex questions which ecologists ask do not come easily. Increasingly though, they arise in direct proportion to the efforts expended upon their elucidation. Many studies have achieved such a high level of elegance, in terms of manpower and apparatus, that there is a feeling that questions asked when such resources are unavailable are not worth asking. Nothing could be further from the truth. Many a complex model has failed fully to explain the phenomenon for which it was construc ted because of a lack of basic field data on the species' natural h~story.