© Copyright 2001 by the Massachusetts Institute of Technology and Yale University Volume 4, Number 3 y FORUM Journal of Industrial Ecology 35 y Summary Industrial ecologists study phenomena at several distinct scales, and linking the resulting insights could advance the field. The disciplines of ecology and economics have each attempted, with partial success, to accomplish this by build- ing a behavioral micro foundation, and industrial ecology should do the same. These fields all study evolving systems made up of autonomous individuals who operate in a largely self-interested manner, exhibit diverse behaviors, and self-organize many higher-level structures such as commu- nities or sectors in a bottom-up fashion. Industrial ecologists should explicitly attempt to integrate empirical and norma- tive views about agency, and more carefully distinguish be- tween two types of agents firms and individual humans. y Building a Micro Foundation for Industrial Ecology Clinton J. Andrews Dept. of Urban Planning and Policy Development Rutgers University New Brunswick, NJ, USA Address correspondence to: Clinton J. Andrews Dept. of Urban Planning and Policy Development Rutgers University 33 Livingston Ave. New Brunswick, NJ 08901 USA cja1@rci.rutgers.edu http://radburn.rutgers.edu/andrews/ Keywords agency biological analogy ethology microeconomics organizational behavior transaction costs