World-wide use of various fertilizers has made a tremendous contribution in enhancing food production. Nutrient inputs are responsible about 30 to 50 % contribution to crop yield. However, fertilizer use efficiency is low. This can be increased by various fertilizer management strategies viz. proper rate, time and method of fertilizer application. However, these fertilizer management strategies do not take into account the inherent soil fertility variation. Site-specific nutrient management approaches can also improve nutrient use efficiency. Usually, fertilizer recommendations developed for various crops tell about the rates of nutrients required on hectare basis and their time of application. This monograph has been written for the graduate and undergraduate students and researchers. I hope this will help the students and researchers for the formulation of fertilizer recommendations based on the spatial variability of soil fertility and other edaphic factors.