SIMPLE questions often help us to understand problems better; and I think it indispensable, at the beginning of this work, to ask a question which appears simple in the extreme: "What is grazing?" The answer is generally as follows: "Causing grass to be eaten by an animal." That is correct! But here is another answer which, to my mind, is more realistic: "Causing the grass and the animal to meet." Since this book is almost exclusively concerned with grazing by cattle, I propose the following definition to the reader, requesting him to allow it to become well impressed upon his mind: Grazing is the meeting of cow and grass. It is by satisfying as far as possible the demands of both parties that we will arrive at a rational grazing, which will provide us with maximum productivity on the part of the grass while at the same time allowing the cow to give optimum performance. [From the Introduction]