This introduction presents an overview of the key concepts discussed in the subsequent chapters of this book. The book deals with selling monopoly, although it will hold good for that of buying also. It discusses the special type of competition between a few enterprises where the individual entrepreneur, like the absolute monopolist, interested in a limitation of the sales. The book focuses on the special kind of adjustment when a couple of enterprises stand face to face as buyer and seller or as sellers of complementary services—bilateral monopoly. It explains the instances where such enterprises cannot arrive at an adjustment by means of a variation in the extent of the sales, but where the decision is obtained by fighting, or threatening to fight. Simplification and abstraction are necessary, in order to bring out as clearly and comprehensibly as possible the quantitative relationship between the different forces at work.