Agricultural research has enormous potential for improving Sub-Saharan African countries' agricultural performance, thereby, stimulating agricultural growth and development. For this potential to be realized, clear policy action is required to accelerate the generation and adoption of new technologies. This calls for, in the first place, evaluation of past research efforts to expose weaknesses that need to be redressed. Secondly, if agricultural research is to contribute positively to agricultural development, research resources have to be allocated efficiently among competing research program alternatives. This requires an informed decision-making tool. This study examined the evolution and performance of agricultural research in Zimbabwe up to 1980. A preliminary qualitative assessment showed that agricultural research contributed significantly to the agricultural development of the country. Crop and livestock research programs initiated in the early 1920's resulted in an increase in crop area and yield as well as livestock productivity. Indigenous improved crop varieties and livestock species adapted to the agro-physical environment have been developed. Research outcome was more spectacular in the large scale commercial farming sector because, prior to 1980, investments in research and extension were biased towards this sector. An evaluation and planning framework proposed in the study is aimed at developing a research resource allocation decision tool that evaluated agricultural research periodically with the results used as a basis for resource allocation and research management.