This paper presents a framework for understanding the value systems inherent in landscape architectural practice. It is based upon a close analytical reading of the academic and professional literature, supported by a series of in-depth interviews with mid- and late-career British landscape architects. The empirical results of these interviews will be presented in a future paper. A tripartite classification of values is suggested, based upon the categories of the aesthetic, the social and the environmental, each of which is internally complex. (...) This framework is offered as a tool for future landscape architectural criticism. The relationships between values both within and between these value areas are discussed. The conclusion reached is that there is no overarching value which can be used to arbitrate between conflicting values. However, while it is possible to identify areas where values conflict, there can also be significant convergence between aesthetic, social and ecological values, and the paper suggests that it is possible to create landscapes which have positive value in all three areas. (shrink)