This book "Performance of tef influenced by row spacing and NP fertilization" will be useful for students of agronomy, agriculture, scientists, agronomists, development professionals and professionals working in allied fields. With population increasing at an alarming rate, there will be a substantial increase in demand of food, fodder and fiber in future. People with knowledge and professional skills in agronomy will have good demand in the coming years. Tef [Eragrostis tef (Zucc.)] is the most important cereal crop of Ethiopia as it occupies 22.23% of the cultivated land with 18.30% of the total food grain production in the country. Tef provides for over two-thirds of the human food and nutrition in the country and hence it is the staple food crop of Ethiopian population. However the present production system cannot satisfy the high consumer demand with the current national average yield of 1.26 tones per hectare. There is urgent need to enhance production and productivity of tef being the staple food crop of Ethiopia.