Soil degradation on small farms in the Eastern Region of Paraguay is the principal cause of a continuous decrease in crop production. The consequences of this are reduced economic income and increased poverty among rural families. The use of green cover with Conservation Agriculture (CA) in this area has been documented in a publication that describes the principal species of green manures and, at the same time, informs in detail how to insert green manures into small farm production systems according to soil fertility and major crops. It also deals with the residual effect of green manures on main crops and analyzes the economic implications of these practices. The main features of the use of green manure/cover, its advantages, considerations and examples of species used in Paraguay are presented in this entry.