Any discussion on issues involving sustainable agriculture must inevitably deal with the problem of defining sustainability [eds Edwards, Edwards, Madden, Millar & House, 1990]. Unfortunately, as soon as this is attempted, a Pandora's box of philosophical problems start to emerge [Lewins, 1990]. The question - 'What is the meaning of sustainability?' is not easily answered as definite answers often cannot be given, but following the works of Edwards et al. [eds 1990], Roberts [1995], Campbell [1994] and Reeve [1990], some of the assumptions of different authors' interpretations will be clarified and related to sustainable agriculture wherever possible. It is very probable that the reason why there is so much confusion over the concept of sustainability, is because the application of this word pertains to the future and is subject to individual definitions and interpretations [ed. Hampson, 1989]. The term 'sustainability' therefore would appear to be a discussion point about agricultural systems for the foreseeable future [Reeve, 1990].

This document also considers the meaning of 'sustainable agriculture' which appears to be problematic, for while it is both arbitrary and intangible, it is also heavily value laden. This has led to an apparent conflict of ideas, ill-defined meanings and a host of countervailing forces [Wilson, 1988; Campbell, 1994; eds Edwards et al. 1990]. To give a hint of the complexity of defining 'sustainable agriculture' there are literally dozens of definitions that have been used with varying degrees of success. The apparent confusion over the meaning, is not surprising as this subject is only a relatively young science. This should not, however, take away from the constant challenge of identifying and interpreting definitions that are still evolving from a diversity of information [UNE, 1992; eds Edwards et al. 1990].

The definition of these words and terms is a challenging part of this work. Considerable attention is devoted to this issue, especially at the commencement of this document. The first term to be considered is the meaning of 'sustainability' and this is discussed by placing it within the conceptual framework of sustainable development that appears to be a natural progression of the ongoing debate concerning sustainability. This is achieved by further exploration of such issues as economic progress, intergenerational equity, biodiversity, and the global dimension. Discussion on sustainable development gives a comprehensive illustration of the multiplicity of views and assumptions involved. Sustainability is also relevant to the term 'sustainable agriculture' and the meaning of the word agri-culture is examined from its Latin origins to its modern interpretation. In the modern interpretation of sustainability, its application to agriculture is generally agreed to be a worthwhile goal [Roberts, 1995], but the practicality of it is open to debate as the following will show. Finally, the meaning, problems and challenges to sustainable agriculture are discussed.