1. Research Associate, Dept. of Civil, Construction, and Environmental Engineering, North Carolina State Univ., Raleigh, NC 27695.
2. Associate Professor, Dept. of Civil, Construction, and Environmental Engineering, North Carolina State Univ., Raleigh, NC 27695 (corresponding author).
3. Former President, Lean Construction Institute, 1400 N. 14th St., #400, Arlington, VA 22209.