Agricultural production, productivity and its sustained development depend on the advancement of science and technology that will enhance production, processing, handling, transportation, distribution and marketing processes of strategically important crops. One of the economical cereal crops in Ethiopia is tef. It is indigenous to the country, and is a fundamental part of the culture, tradition, and food security of the people. In order to get higher yield in tef production, improved modern management system and technological inputs starting from land preparation to storage must be employed efficiently and appropriately in order to reduce harvesting losses, in addition to reducing work drudgery that consumes more time, labour and energy of the farming society during traditional method of separation and cleaning. So this book incorporates the problems associated with chaff, straw, dirt and dust separation and cleaning tef grain with the designed and developed a machine that can separate undesired materials and clean tef grain after threshing using either manual, animal or mechanical means.