Agriculture as a productive activity may affect actively both the degradation and the preservation of the environment and natural resources. These latter (soil, water, etc.) are factors relevant to agriculture, therefore, their deterioration may lead to serious economic problems for this could jeopardize our future productive potential. At present, conventional agriculture is questioned due to its degrading effect on natural resources and on the environment in general. There is currently a development of alternative systems for agricultural production, generally known as sustainable agriculture. From a basically agro-ecological and economic standpoint, we are now studying the problems that the transition from conventional to sustainable agriculture may pose, taking into account the different existing circumstances, which depend on the degree of economic development of different countries.