Studies on the relationship between society and the environment (in general) and on sustainability issues (in particular) are characteristically interdisciplinary or, more precisely, transdisciplinary.

The reasons for the above assessment can be summarised as follows: The research on the relationship between environment and society involves the analysis of the social effects of changes in the natural environment, and the impact of social transformations and changes on it. It is therefore a matter that lies on the threshold between the two great fields of modern science, the natural sciences and the social or human sciences, two fields which have been increasingly separated for a long time.

This border condition immediately raises the question of the opportunities for a new approach between these two worlds that have turned their backs on each other, as well as the conditions and limits of such approach. Biologist E.O. Wilson has put it this way: "The connection of the latter field [sustainability studies] with social theory may seem weak at first, but it is not weak at all. The natural environment is the theatre in which the human species evolved and to which its physiology and behaviour are finally adapted. Neither human biology nor the social sciences can make full sense until their worldviews take account of that unyielding framework".

The relationship between society and environment is mainly summed up in the discussion regarding the concept of sustainability. This relationship has different mediations. If we start with issues more proper to human ecology, the question of the carrying capacity for human beings (sustainable population) can be raised. Even if there must be natural limits in this field, it is clear that they can change according to the characteristics of the available techniques: in the human species, biology is not independent of technology.

One consequence of technology –the proliferation of devices irrevocably associated with human bodies– has a notable implication: some people may have much larger exosomatic extensions than others. Inequality and social conflict thus take part in the analysis: biology is not separable from technology, sociology or politics.

On the other hand, the belief that social action can stem the ecological crisis depends on the assumption that the human species –unlike any other– is capable of finding sources of resources in its environment without exploiting them to exhaustion, i.e. that the structure of needs can be regulated for reasons other than the existence or lack of means to satisfy them (or, in other words, that responses to environmental stimuli are not rigidly programmed into the genetic endowment of humans).

We are thus in the realm of culture (of lifestyles and consumption, of values and also of myths). Within the framework of a general examination of the relationships between society and nature, all these levels of analysis have relevant dimensions and cannot be ignored. It is quite clear, then, that no particular science, with its current instruments and categories, is in a position to deal with all aspects of such a subject of knowledge. The most adequate alternative is an attempt at mutual compatibility without reductionisms (without any privileged disciplinary perspective). This is more than just a mere interdisciplinary assault, but also much less than the reappearance of a unified science.