The development is sustainable when it satisfies the necessities of the present generation without jeopardizing the capacity of the future generations to satisfy their own necessities.
Informe Bruntland, 1987.
Comisión Mundial sobre Medio Ambiente y Desarrollo ONU.

Sustainable farming and rural development is the administration and conservation of the base of natural resources and the direction of the technological and institutional changes of such form that the permanent gathering and the satisfaction assure the human necessities for the present and the future generations.

This sustainable development (in the sectors farming, forest and fishing) conserves Earth, water, genetic resources of the animal and vegetable gendre, does not degrade the environment, is technologically appropriate, economically viable and socially acceptable.

FAO, 1992.

Development is a dynamic process, in permanent unbalance, that tends to the increase of the conditions of life of all the population of the world…

sustainability is the possibility of maintaining productive and social processes during generational lapses, obtaining from these processes equal or more resources... reaching an even situation of development of the humanity, in terms of substantive improvement of the levels and quality of life.

The sustainable development... in addition to being endogenous, is to say been born and suitable to the local specifications, and self-managed, that is to say, planned executed and administered by the own subjects of the complex.

Economic sustainability, to have the resources necessary to give persistence to the process;

Ecological sustainability, to protect the base of natural resources being watched towards the future and preventing, without without stop them, the genetic resources, (human, forest, fishing, microbiological) water and ground;

Power sustainability, investigating, designing and using technologies that consume equal or less energy than the one than it produces, fundamental in the case of the rural development and that, in addition, does not attack by means of their use to the other elements of the system;

Social sustainability, so that the models of development and the resources derived from it benefit all humanity, the same that is to say, fairness;

Cultural sustainability, favoring the diversity and specificity of local, regional, national and international manifestations, without restricting the culture at a particular level of activities, but including in it a greater variety of human activities;

Scientific sustainability, by the unrestricted support to the investigation in pure science as much as in the technological applied one and, without allowing that first one to be oriented exclusively by criteria of immediate and short term yield.

J.M. Calvelo Rios, 1998.