The consensus at the Third Annual Conference of IGLC was that a Lean Construction (LC) philosophy and practice, distinct from existing construction praxes, are beginning to emerge. The need was identified to articulate and refine LC theory. In an attempt to contribute to the pursuit of this aim , the paper elaborates the proposition that a characteristic of existing organization and management theory is its inability to provide an adequate account of its own praxis. This is so because such theory is rooted in the rationalist or Cartesian paradigm which assumes the possibility of distinguishing between objective and subjective, and is, therefore, unable to address the actual processes, dynamics and so on that currently exist. In particular, there is a need to clarify, through empirical study, the relationship between research and its associated theory building and practice. Thus, there follow two issues which must form part of the LC agenda. First, a much more detailed understanding of current practice is necessary. Second, LC researchers, in pursuing their essentially action-oriented or developmental approach, in which the demonstration of practical benefit is at a premium, must be careful not to fall into the rationalist trap. This will be achieved to the extent that whatever theory they develop reflects the empirical realities that constitute the processes in which they are involved.
lean Construction, rationalist philosophy, theory, method, socio-technical systems, practical reasoning