This report is not intended to be a definitive review of published literature concerning environmental changes which might occur in northern ecosystems as a result of massive industrial development. Rather, it is intended to summarize a large number of surveys and some research of a distinctly applied nature and to describe the manner in which the Alberta Oil Sands Environmental Research Program (AOSERP) was carried out. The level of impact reported to date is described in a manner which allows environmental managers in government and industry to decide what additional research may be required to support future environmental management decisions. It was not possible with available data and within the terms of reference for this report to predict the consequences of future massive development of the Athabasca Oil Sands; to do so would be speculative. The position is taken a priority in organizing this report that the AOSERP systems approach to environmental research points the way to description of air, land, water, and human systems in terms (conceptually at least) of dynamic models, which may be useful in directing future research and in assessing long-term environmental effects of development of the Athabasca Oil Sands. Such an approach lends itself to computer simulation modelling which may be used to develop alternative predictive impact scenarios and research options, without prior committal of large research budgets. The systems approach used by AOSERP is only the first step toward any in-depth assessment of ecosystems and social impacts – an administrative convenience for organizing a complex series of investigations. In order to assess with any degree of exactitude what the long-term impacts of oil sands development might be, extensive research will be required to develop a predictive capability which does not now exist. Some of the obvious gaps in research knowledge are discussed and recommendations advanced which might aid in correcting these deficiencies. This report provides background information which describes the initiation and conduct of AOSERP from 1975 to 1980. The program amassed a very large amount of baseline information over its five-year life, at a cost of about $17.4 million. The assessment is made that baseline information on the Athabasca Oil Sands region is now complete enough that additional general surveys will not be required in future. Rather, recommendations are advanced for specific applied research projects. Systems research results are described below in relation to possible effects on ecosystems and people. Recommendations for future environmental research have been made on the assumption that continued massive development of the Athabasca Oil Sands will take place. The proposition is advanced that the present level of spending on environmental research by industry and government should be maintained as an investment in the maintenance of acceptable environmental quality for the region.